Add saved runs feature with history, comparison, and about screen (v1.2)

Features:
- Save calculation runs with custom labels for later retrieval
- View saved runs list with dominant factor summary
- View detailed results of any saved run
- View original inputs in read-only mode
- Use any saved run as starting point for new calculation
- Compare two saved runs side-by-side
- About screen with app info, help links, privacy policy
- Metric/Imperial unit toggle persisted across sessions
- Info icon in app bar on all screens

Technical:
- New SavedRun model with full serialization
- SQLite saved_runs table with CRUD operations
- readOnly mode for all input screens
- Unit preference stored in LocalStorage
- Database schema upgraded to v2

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/models/models.dart

@@ -2,3 +2,4 @@ export 'enums.dart';
 export 'user_profile.dart';
 export 'behavioral_inputs.dart';
 export 'result.dart';
+export 'saved_run.dart';

lib/models/saved_run.dart

@@ -0,0 +1,80 @@
+import 'behavioral_inputs.dart';
+import 'result.dart';
+import 'user_profile.dart';
+
+class SavedRun {
+  final String id;
+  final String label;
+  final CalculationResult result;
+  final UserProfile profile;
+  final BehavioralInputs behaviors;
+  final DateTime createdAt;
+
+  const SavedRun({
+    required this.id,
+    required this.label,
+    required this.result,
+    required this.profile,
+    required this.behaviors,
+    required this.createdAt,
+  });
+
+  String get displayDate {
+    final now = DateTime.now();
+    final diff = now.difference(createdAt);
+
+    if (diff.inDays == 0) {
+      return 'Today';
+    } else if (diff.inDays == 1) {
+      return 'Yesterday';
+    } else if (diff.inDays < 7) {
+      return '${diff.inDays} days ago';
+    } else {
+      return '${createdAt.month}/${createdAt.day}/${createdAt.year}';
+    }
+  }
+
+  String get dominantFactorSummary {
+    final factor = result.dominantFactor;
+    if (factor == null) return 'Optimal';
+    return '${factor.displayName}: ${factor.delta.rangeDisplay} mo';
+  }
+
+  Map<String, dynamic> toJson() => {
+        'id': id,
+        'label': label,
+        'result': result.toJson(),
+        'profile': profile.toJson(),
+        'behaviors': behaviors.toJson(),
+        'createdAt': createdAt.toIso8601String(),
+      };
+
+  factory SavedRun.fromJson(Map<String, dynamic> json) => SavedRun(
+        id: json['id'] as String,
+        label: json['label'] as String,
+        result:
+            CalculationResult.fromJson(json['result'] as Map<String, dynamic>),
+        profile:
+            UserProfile.fromJson(json['profile'] as Map<String, dynamic>),
+        behaviors: BehavioralInputs.fromJson(
+            json['behaviors'] as Map<String, dynamic>),
+        createdAt: DateTime.parse(json['createdAt'] as String),
+      );
+
+  SavedRun copyWith({
+    String? id,
+    String? label,
+    CalculationResult? result,
+    UserProfile? profile,
+    BehavioralInputs? behaviors,
+    DateTime? createdAt,
+  }) =>
+      SavedRun(
+        id: id ?? this.id,
+        label: label ?? this.label,
+        result: result ?? this.result,
+        profile: profile ?? this.profile,
+        behaviors: behaviors ?? this.behaviors,
+        createdAt: createdAt ?? this.createdAt,
+      );
+}

lib/screens/about_screen.dart

@@ -0,0 +1,196 @@
+import 'package:flutter/material.dart';
+import 'package:url_launcher/url_launcher.dart';
+import '../theme.dart';
+
+class AboutScreen extends StatelessWidget {
+  const AboutScreen({super.key});
+
+  static const String _helpUrl = 'https://addmonths.app/help';
+  static const String _privacyUrl = 'https://addmonths.app/privacy';
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('About'),
+        leading: IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: () => Navigator.pop(context),
+        ),
+      ),
+      body: SingleChildScrollView(
+        padding: const EdgeInsets.all(24),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            // App name and version
+            Center(
+              child: Column(
+                children: [
+                  Container(
+                    width: 80,
+                    height: 80,
+                    decoration: BoxDecoration(
+                      color: AppColors.surfaceVariant,
+                      borderRadius: BorderRadius.circular(20),
+                    ),
+                    child: const Icon(
+                      Icons.timeline,
+                      size: 40,
+                      color: AppColors.primary,
+                    ),
+                  ),
+                  const SizedBox(height: 16),
+                  Text(
+                    'Add Months',
+                    style: Theme.of(context).textTheme.headlineMedium,
+                  ),
+                  const SizedBox(height: 4),
+                  Text(
+                    'Version 1.2',
+                    style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                          color: AppColors.textSecondary,
+                        ),
+                  ),
+                ],
+              ),
+            ),
+            const SizedBox(height: 32),
+
+            // Description
+            Text(
+              'What is Add Months?',
+              style: Theme.of(context).textTheme.titleMedium,
+            ),
+            const SizedBox(height: 8),
+            Text(
+              'Add Months uses evidence-based hazard ratios from peer-reviewed '
+              'meta-analyses to identify which single lifestyle change could '
+              'have the biggest impact on your lifespan.',
+              style: Theme.of(context).textTheme.bodyMedium,
+            ),
+            const SizedBox(height: 16),
+            Text(
+              'Answer simple questions about your demographics and habits, '
+              'and the app calculates which modifiable factor offers the '
+              'greatest potential benefit.',
+              style: Theme.of(context).textTheme.bodyMedium,
+            ),
+            const SizedBox(height: 32),
+
+            // Privacy note
+            Container(
+              padding: const EdgeInsets.all(16),
+              decoration: BoxDecoration(
+                color: AppColors.surfaceVariant,
+                borderRadius: BorderRadius.circular(12),
+              ),
+              child: Row(
+                children: [
+                  const Icon(
+                    Icons.lock_outline,
+                    color: AppColors.primary,
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Text(
+                          'Your data stays on your device',
+                          style: Theme.of(context).textTheme.titleSmall,
+                        ),
+                        const SizedBox(height: 4),
+                        Text(
+                          'No accounts, no cloud sync, no analytics. '
+                          'Everything is stored locally.',
+                          style: Theme.of(context).textTheme.bodySmall,
+                        ),
+                      ],
+                    ),
+                  ),
+                ],
+              ),
+            ),
+            const SizedBox(height: 32),
+
+            // Links
+            _buildLinkButton(
+              context,
+              icon: Icons.help_outline,
+              label: 'How it works',
+              onTap: () => _launchUrl(_helpUrl),
+            ),
+            const SizedBox(height: 12),
+            _buildLinkButton(
+              context,
+              icon: Icons.privacy_tip_outlined,
+              label: 'Privacy Policy',
+              onTap: () => _launchUrl(_privacyUrl),
+            ),
+            const SizedBox(height: 32),
+
+            // Disclaimer
+            Text(
+              'Disclaimer',
+              style: Theme.of(context).textTheme.titleSmall?.copyWith(
+                    color: AppColors.textSecondary,
+                  ),
+            ),
+            const SizedBox(height: 8),
+            Text(
+              'This app provides general information based on population-level '
+              'research and is not medical advice. Individual results vary widely. '
+              'Consult a healthcare provider for personalized guidance.',
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: AppColors.textSecondary,
+                  ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildLinkButton(
+    BuildContext context, {
+    required IconData icon,
+    required String label,
+    required VoidCallback onTap,
+  }) {
+    return InkWell(
+      onTap: onTap,
+      borderRadius: BorderRadius.circular(12),
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
+        decoration: BoxDecoration(
+          border: Border.all(color: AppColors.divider),
+          borderRadius: BorderRadius.circular(12),
+        ),
+        child: Row(
+          children: [
+            Icon(icon, color: AppColors.primary),
+            const SizedBox(width: 12),
+            Text(
+              label,
+              style: Theme.of(context).textTheme.bodyLarge,
+            ),
+            const Spacer(),
+            const Icon(
+              Icons.open_in_new,
+              size: 18,
+              color: AppColors.textSecondary,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Future<void> _launchUrl(String url) async {
+    final uri = Uri.parse(url);
+    if (await canLaunchUrl(uri)) {
+      await launchUrl(uri, mode: LaunchMode.externalApplication);
+    }
+  }
+}

lib/screens/baseline_screen.dart

@@ -3,10 +3,18 @@ import '../models/models.dart';
 import '../risk_engine/mortality_tables.dart';
 import '../storage/local_storage.dart';
 import '../theme.dart';
+import 'about_screen.dart';
 import 'behavioral_screen.dart';
 
 class BaselineScreen extends StatefulWidget {
-  const BaselineScreen({super.key});
+  final bool readOnly;
+  final UserProfile? initialProfile;
+
+  const BaselineScreen({
+    super.key,
+    this.readOnly = false,
+    this.initialProfile,
+  });
 
   @override
   State<BaselineScreen> createState() => _BaselineScreenState();
@@ -19,6 +27,7 @@ class _BaselineScreenState extends State<BaselineScreen> {
   double _heightCm = 170;
   double _weightKg = 70;
   final Set<Diagnosis> _diagnoses = {};
+  bool _useMetric = false;
 
   late List<String> _countries;
 
@@ -26,24 +35,39 @@ class _BaselineScreenState extends State<BaselineScreen> {
   void initState() {
     super.initState();
     _countries = getSupportedCountries();
-    _loadExistingProfile();
+    _loadInitialData();
   }
 
-  Future<void> _loadExistingProfile() async {
+  Future<void> _loadInitialData() async {
+    // Load unit preference
+    final useMetric = await LocalStorage.getUseMetricUnits();
+    setState(() => _useMetric = useMetric);
+
+    // If initial profile provided, use that
+    if (widget.initialProfile != null) {
+      _applyProfile(widget.initialProfile!);
+      return;
+    }
+
+    // Otherwise load from storage
     final profile = await LocalStorage.getProfile();
     if (profile != null) {
-      setState(() {
+      _applyProfile(profile);
-        _age = profile.age;
-        _sex = profile.sex;
-        _country = profile.country;
-        _heightCm = profile.heightCm;
-        _weightKg = profile.weightKg;
-        _diagnoses.clear();
-        _diagnoses.addAll(profile.diagnoses);
-      });
     }
   }
 
+  void _applyProfile(UserProfile profile) {
+    setState(() {
+      _age = profile.age;
+      _sex = profile.sex;
+      _country = profile.country;
+      _heightCm = profile.heightCm;
+      _weightKg = profile.weightKg;
+      _diagnoses.clear();
+      _diagnoses.addAll(profile.diagnoses);
+    });
+  }
+
   double get _bmi => _weightKg / ((_heightCm / 100) * (_heightCm / 100));
 
   String get _bmiCategory {
@@ -59,11 +83,25 @@ class _BaselineScreenState extends State<BaselineScreen> {
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text('Baseline'),
+        title: Text(widget.readOnly ? 'Baseline (View Only)' : 'Baseline'),
         leading: IconButton(
           icon: const Icon(Icons.arrow_back),
           onPressed: () => Navigator.pop(context),
         ),
+        actions: [
+          IconButton(
+            icon: Icon(_useMetric ? Icons.straighten : Icons.square_foot),
+            tooltip: _useMetric ? 'Using Metric' : 'Using Imperial',
+            onPressed: widget.readOnly ? null : _toggleUnits,
+          ),
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
       ),
       body: SingleChildScrollView(
         padding: const EdgeInsets.all(24),
@@ -129,14 +167,15 @@ class _BaselineScreenState extends State<BaselineScreen> {
             _buildDiagnosisCheckboxes(),
             const SizedBox(height: 32),
 
-            // Continue button
+            // Continue button (hidden in readOnly mode)
-            SizedBox(
+            if (!widget.readOnly)
-              width: double.infinity,
+              SizedBox(
-              child: ElevatedButton(
+                width: double.infinity,
-                onPressed: _continue,
+                child: ElevatedButton(
-                child: const Text('Continue'),
+                  onPressed: _continue,
+                  child: const Text('Continue'),
+                ),
               ),
-            ),
             const SizedBox(height: 16),
           ],
         ),
@@ -162,7 +201,9 @@ class _BaselineScreenState extends State<BaselineScreen> {
         children: [
           IconButton(
             icon: const Icon(Icons.remove),
-            onPressed: _age > 18 ? () => setState(() => _age--) : null,
+            onPressed: widget.readOnly || _age <= 18
+                ? null
+                : () => setState(() => _age--),
           ),
           Expanded(
             child: Text(
@@ -173,7 +214,9 @@ class _BaselineScreenState extends State<BaselineScreen> {
           ),
           IconButton(
             icon: const Icon(Icons.add),
-            onPressed: _age < 100 ? () => setState(() => _age++) : null,
+            onPressed: widget.readOnly || _age >= 100
+                ? null
+                : () => setState(() => _age++),
           ),
         ],
       ),
@@ -187,7 +230,7 @@ class _BaselineScreenState extends State<BaselineScreen> {
           child: _buildToggleButton(
             'Male',
             _sex == Sex.male,
-            () => setState(() => _sex = Sex.male),
+            widget.readOnly ? null : () => setState(() => _sex = Sex.male),
           ),
         ),
         const SizedBox(width: 12),
@@ -195,14 +238,14 @@ class _BaselineScreenState extends State<BaselineScreen> {
           child: _buildToggleButton(
             'Female',
             _sex == Sex.female,
-            () => setState(() => _sex = Sex.female),
+            widget.readOnly ? null : () => setState(() => _sex = Sex.female),
           ),
         ),
       ],
     );
   }
 
-  Widget _buildToggleButton(String label, bool selected, VoidCallback onTap) {
+  Widget _buildToggleButton(String label, bool selected, VoidCallback? onTap) {
     return GestureDetector(
       onTap: onTap,
       child: Container(
@@ -242,26 +285,35 @@ class _BaselineScreenState extends State<BaselineScreen> {
               child: Text(country),
             );
           }).toList(),
-          onChanged: (value) {
+          onChanged: widget.readOnly
-            if (value != null) setState(() => _country = value);
+              ? null
-          },
+              : (value) {
+                  if (value != null) setState(() => _country = value);
+                },
         ),
       ),
     );
   }
 
   Widget _buildHeightSlider() {
+    final primaryText = _useMetric
+        ? '${_heightCm.round()} cm'
+        : _cmToFeetInches(_heightCm);
+    final secondaryText = _useMetric
+        ? _cmToFeetInches(_heightCm)
+        : '${_heightCm.round()} cm';
+
     return Column(
       children: [
         Row(
           mainAxisAlignment: MainAxisAlignment.spaceBetween,
           children: [
             Text(
-              '${_heightCm.round()} cm',
+              primaryText,
               style: Theme.of(context).textTheme.headlineMedium,
             ),
             Text(
-              _cmToFeetInches(_heightCm),
+              secondaryText,
               style: Theme.of(context).textTheme.bodyMedium,
             ),
           ],
@@ -271,24 +323,30 @@ class _BaselineScreenState extends State<BaselineScreen> {
           min: 120,
           max: 220,
           divisions: 100,
-          onChanged: (value) => setState(() => _heightCm = value),
+          onChanged: widget.readOnly
+              ? null
+              : (value) => setState(() => _heightCm = value),
         ),
       ],
     );
   }
 
   Widget _buildWeightSlider() {
+    final lbs = (_weightKg * 2.205).round();
+    final primaryText = _useMetric ? '${_weightKg.round()} kg' : '$lbs lbs';
+    final secondaryText = _useMetric ? '$lbs lbs' : '${_weightKg.round()} kg';
+
     return Column(
       children: [
         Row(
           mainAxisAlignment: MainAxisAlignment.spaceBetween,
           children: [
             Text(
-              '${_weightKg.round()} kg',
+              primaryText,
               style: Theme.of(context).textTheme.headlineMedium,
             ),
             Text(
-              '${(_weightKg * 2.205).round()} lbs',
+              secondaryText,
               style: Theme.of(context).textTheme.bodyMedium,
             ),
           ],
@@ -298,7 +356,9 @@ class _BaselineScreenState extends State<BaselineScreen> {
           min: 30,
           max: 200,
           divisions: 170,
-          onChanged: (value) => setState(() => _weightKg = value),
+          onChanged: widget.readOnly
+              ? null
+              : (value) => setState(() => _weightKg = value),
         ),
       ],
     );
@@ -357,15 +417,17 @@ class _BaselineScreenState extends State<BaselineScreen> {
       children: Diagnosis.values.map((diagnosis) {
         return CheckboxListTile(
           value: _diagnoses.contains(diagnosis),
-          onChanged: (checked) {
+          onChanged: widget.readOnly
-            setState(() {
+              ? null
-              if (checked == true) {
+              : (checked) {
-                _diagnoses.add(diagnosis);
+                  setState(() {
-              } else {
+                    if (checked == true) {
-                _diagnoses.remove(diagnosis);
+                      _diagnoses.add(diagnosis);
-              }
+                    } else {
-            });
+                      _diagnoses.remove(diagnosis);
-          },
+                    }
+                  });
+                },
           title: Text(_getDiagnosisLabel(diagnosis)),
           controlAffinity: ListTileControlAffinity.leading,
           contentPadding: EdgeInsets.zero,
@@ -396,6 +458,12 @@ class _BaselineScreenState extends State<BaselineScreen> {
     return "$feet'$inches\"";
   }
 
+  Future<void> _toggleUnits() async {
+    final newValue = !_useMetric;
+    await LocalStorage.setUseMetricUnits(newValue);
+    setState(() => _useMetric = newValue);
+  }
+
   void _continue() async {
     final profile = UserProfile(
       age: _age,

lib/screens/behavioral_screen.dart

@@ -3,12 +3,20 @@ import 'package:flutter/services.dart';
 import '../models/models.dart';
 import '../storage/local_storage.dart';
 import '../theme.dart';
+import 'about_screen.dart';
 import 'lifestyle_screen.dart';
 
 class BehavioralScreen extends StatefulWidget {
   final UserProfile profile;
+  final bool readOnly;
+  final BehavioralInputs? initialBehaviors;
 
-  const BehavioralScreen({super.key, required this.profile});
+  const BehavioralScreen({
+    super.key,
+    required this.profile,
+    this.readOnly = false,
+    this.initialBehaviors,
+  });
 
   @override
   State<BehavioralScreen> createState() => _BehavioralScreenState();
@@ -25,32 +33,52 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
   @override
   void initState() {
     super.initState();
-    _loadExistingBehaviors();
+    _loadInitialData();
   }
 
-  Future<void> _loadExistingBehaviors() async {
+  Future<void> _loadInitialData() async {
+    // If initial behaviors provided, use those
+    if (widget.initialBehaviors != null) {
+      _applyBehaviors(widget.initialBehaviors!);
+      return;
+    }
+
+    // Otherwise load from storage
     final behaviors = await LocalStorage.getBehaviors();
     if (behaviors != null) {
-      setState(() {
+      _applyBehaviors(behaviors);
-        _smoking = behaviors.smoking;
-        _cigarettesPerDay = behaviors.cigarettesPerDay;
-        _alcohol = behaviors.alcohol;
-        _sleepHours = behaviors.sleepHours;
-        _sleepConsistent = behaviors.sleepConsistent;
-        _activity = behaviors.activity;
-      });
     }
   }
 
+  void _applyBehaviors(BehavioralInputs behaviors) {
+    setState(() {
+      _smoking = behaviors.smoking;
+      _cigarettesPerDay = behaviors.cigarettesPerDay;
+      _alcohol = behaviors.alcohol;
+      _sleepHours = behaviors.sleepHours;
+      _sleepConsistent = behaviors.sleepConsistent;
+      _activity = behaviors.activity;
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text('Habits'),
+        title: Text(widget.readOnly ? 'Habits (View Only)' : 'Habits'),
         leading: IconButton(
           icon: const Icon(Icons.arrow_back),
           onPressed: () => Navigator.pop(context),
         ),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
       ),
       body: SingleChildScrollView(
         padding: const EdgeInsets.all(24),
@@ -98,14 +126,15 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
             _buildActivitySelector(),
             const SizedBox(height: 40),
 
-            // Continue button
+            // Continue button (hidden in readOnly mode)
-            SizedBox(
+            if (!widget.readOnly)
-              width: double.infinity,
+              SizedBox(
-              child: ElevatedButton(
+                width: double.infinity,
-                onPressed: _continue,
+                child: ElevatedButton(
-                child: const Text('Continue'),
+                  onPressed: _continue,
+                  child: const Text('Continue'),
+                ),
               ),
-            ),
             const SizedBox(height: 16),
           ],
         ),
@@ -128,7 +157,7 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
         (SmokingStatus.former, 'Former'),
         (SmokingStatus.current, 'Current'),
       ],
-      onChanged: (value) => setState(() => _smoking = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _smoking = value),
     );
   }
 
@@ -149,12 +178,14 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
                 min: 1,
                 max: 40,
                 divisions: 39,
-                onChanged: (value) {
+                onChanged: widget.readOnly
-                  if (value.round() == 20 && _cigarettesPerDay != 20) {
+                    ? null
-                    HapticFeedback.mediumImpact();
+                    : (value) {
-                  }
+                        if (value.round() == 20 && _cigarettesPerDay != 20) {
-                  setState(() => _cigarettesPerDay = value.round());
+                          HapticFeedback.mediumImpact();
-                },
+                        }
+                        setState(() => _cigarettesPerDay = value.round());
+                      },
               ),
             ),
             SizedBox(
@@ -187,7 +218,7 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
         (AlcoholLevel.heavy, '15-21'),
         (AlcoholLevel.veryHeavy, '21+'),
       ],
-      onChanged: (value) => setState(() => _alcohol = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _alcohol = value),
     );
   }
 
@@ -212,7 +243,9 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
           min: 4,
           max: 12,
           divisions: 16,
-          onChanged: (value) => setState(() => _sleepHours = value),
+          onChanged: widget.readOnly
+              ? null
+              : (value) => setState(() => _sleepHours = value),
         ),
       ],
     );
@@ -228,7 +261,9 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
         ),
         Switch(
           value: _sleepConsistent,
-          onChanged: (value) => setState(() => _sleepConsistent = value),
+          onChanged: widget.readOnly
+              ? null
+              : (value) => setState(() => _sleepConsistent = value),
         ),
       ],
     );
@@ -243,14 +278,14 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
         (ActivityLevel.moderate, 'Moderate'),
         (ActivityLevel.high, 'High'),
       ],
-      onChanged: (value) => setState(() => _activity = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _activity = value),
     );
   }
 
   Widget _buildSegmentedControl<T>({
     required T value,
     required List<(T, String)> options,
-    required ValueChanged<T> onChanged,
+    required ValueChanged<T>? onChanged,
   }) {
     return Container(
       decoration: BoxDecoration(
@@ -262,7 +297,7 @@ class _BehavioralScreenState extends State<BehavioralScreen> {
           final isSelected = value == option.$1;
           return Expanded(
             child: GestureDetector(
-              onTap: () => onChanged(option.$1),
+              onTap: onChanged == null ? null : () => onChanged(option.$1),
               child: Container(
                 padding: const EdgeInsets.symmetric(vertical: 12),
                 decoration: BoxDecoration(

lib/screens/compare_runs_screen.dart

@@ -0,0 +1,350 @@
+import 'package:flutter/material.dart';
+import '../models/models.dart';
+import '../storage/local_storage.dart';
+import '../theme.dart';
+import 'about_screen.dart';
+
+class CompareRunsScreen extends StatefulWidget {
+  final SavedRun initialRun;
+
+  const CompareRunsScreen({super.key, required this.initialRun});
+
+  @override
+  State<CompareRunsScreen> createState() => _CompareRunsScreenState();
+}
+
+class _CompareRunsScreenState extends State<CompareRunsScreen> {
+  List<SavedRun> _allRuns = [];
+  SavedRun? _selectedRun;
+  bool _loading = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _loadRuns();
+  }
+
+  Future<void> _loadRuns() async {
+    final runs = await LocalStorage.getSavedRuns();
+    // Exclude the initial run from selection options
+    final otherRuns = runs.where((r) => r.id != widget.initialRun.id).toList();
+    setState(() {
+      _allRuns = otherRuns;
+      _loading = false;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Compare Runs'),
+        leading: IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: () => Navigator.pop(context),
+        ),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
+      ),
+      body: _loading
+          ? const Center(child: CircularProgressIndicator())
+          : _buildContent(),
+    );
+  }
+
+  Widget _buildContent() {
+    if (_selectedRun == null) {
+      return _buildRunSelector();
+    }
+    return _buildComparison();
+  }
+
+  Widget _buildRunSelector() {
+    return Padding(
+      padding: const EdgeInsets.all(24),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            'Select a run to compare with',
+            style: Theme.of(context).textTheme.headlineSmall,
+          ),
+          const SizedBox(height: 8),
+          Text(
+            'Comparing: ${widget.initialRun.label}',
+            style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                  color: AppColors.primary,
+                ),
+          ),
+          const SizedBox(height: 24),
+          Expanded(
+            child: ListView.builder(
+              itemCount: _allRuns.length,
+              itemBuilder: (context, index) {
+                final run = _allRuns[index];
+                return Card(
+                  margin: const EdgeInsets.only(bottom: 12),
+                  child: ListTile(
+                    title: Text(run.label),
+                    subtitle: Text(run.displayDate),
+                    trailing: const Icon(Icons.chevron_right),
+                    onTap: () => setState(() => _selectedRun = run),
+                  ),
+                );
+              },
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildComparison() {
+    final runA = widget.initialRun;
+    final runB = _selectedRun!;
+
+    return SingleChildScrollView(
+      padding: const EdgeInsets.all(24),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          // Header with run labels
+          Row(
+            children: [
+              Expanded(
+                child: _buildRunHeader(runA, 'Run A'),
+              ),
+              const SizedBox(width: 16),
+              Expanded(
+                child: _buildRunHeader(runB, 'Run B'),
+              ),
+            ],
+          ),
+          const SizedBox(height: 24),
+
+          // Dominant factors comparison
+          Text(
+            'Dominant Challenge',
+            style: Theme.of(context).textTheme.titleMedium,
+          ),
+          const SizedBox(height: 12),
+          _buildDominantComparison(runA, runB),
+          const SizedBox(height: 24),
+
+          // Profile changes
+          Text(
+            'Profile Changes',
+            style: Theme.of(context).textTheme.titleMedium,
+          ),
+          const SizedBox(height: 12),
+          _buildProfileComparison(runA.profile, runB.profile),
+          const SizedBox(height: 32),
+
+          // Change comparison button
+          Center(
+            child: TextButton(
+              onPressed: () => setState(() => _selectedRun = null),
+              child: const Text('Compare with different run'),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildRunHeader(SavedRun run, String tag) {
+    return Container(
+      padding: const EdgeInsets.all(12),
+      decoration: BoxDecoration(
+        color: AppColors.surfaceVariant,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            tag,
+            style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                  color: AppColors.textSecondary,
+                ),
+          ),
+          const SizedBox(height: 4),
+          Text(
+            run.label,
+            style: Theme.of(context).textTheme.titleSmall,
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+          ),
+          Text(
+            run.displayDate,
+            style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                  color: AppColors.textSecondary,
+                ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildDominantComparison(SavedRun runA, SavedRun runB) {
+    final dominantA = runA.result.dominantFactor;
+    final dominantB = runB.result.dominantFactor;
+
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Expanded(
+          child: _buildCompactFactorCard(dominantA),
+        ),
+        const SizedBox(width: 16),
+        Expanded(
+          child: _buildCompactFactorCard(dominantB),
+        ),
+      ],
+    );
+  }
+
+  Widget _buildCompactFactorCard(RankedFactor? factor) {
+    if (factor == null) {
+      return Container(
+        padding: const EdgeInsets.all(16),
+        decoration: BoxDecoration(
+          color: AppColors.success.withAlpha(26),
+          borderRadius: BorderRadius.circular(12),
+        ),
+        child: Column(
+          children: [
+            const Icon(Icons.check_circle, color: AppColors.success),
+            const SizedBox(height: 8),
+            Text(
+              'Optimal',
+              style: Theme.of(context).textTheme.titleSmall?.copyWith(
+                    color: AppColors.success,
+                  ),
+            ),
+          ],
+        ),
+      );
+    }
+
+    return Container(
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: AppColors.primary.withAlpha(26),
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            factor.displayName,
+            style: Theme.of(context).textTheme.titleSmall,
+          ),
+          const SizedBox(height: 4),
+          Text(
+            '${factor.delta.rangeDisplay} mo',
+            style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+                  color: AppColors.primary,
+                ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildProfileComparison(UserProfile profileA, UserProfile profileB) {
+    final changes = <Widget>[];
+
+    if (profileA.age != profileB.age) {
+      changes.add(_buildChangeRow(
+        'Age',
+        '${profileA.age}',
+        '${profileB.age}',
+      ));
+    }
+
+    if (profileA.weightKg != profileB.weightKg) {
+      changes.add(_buildChangeRow(
+        'Weight',
+        '${profileA.weightKg.round()} kg',
+        '${profileB.weightKg.round()} kg',
+      ));
+    }
+
+    if (profileA.country != profileB.country) {
+      changes.add(_buildChangeRow(
+        'Country',
+        profileA.country,
+        profileB.country,
+      ));
+    }
+
+    if (changes.isEmpty) {
+      return Container(
+        padding: const EdgeInsets.all(16),
+        decoration: BoxDecoration(
+          color: AppColors.surfaceVariant,
+          borderRadius: BorderRadius.circular(12),
+        ),
+        child: Center(
+          child: Text(
+            'No profile changes between runs',
+            style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                  color: AppColors.textSecondary,
+                ),
+          ),
+        ),
+      );
+    }
+
+    return Column(children: changes);
+  }
+
+  Widget _buildChangeRow(String label, String valueA, String valueB) {
+    return Container(
+      margin: const EdgeInsets.only(bottom: 8),
+      padding: const EdgeInsets.all(12),
+      decoration: BoxDecoration(
+        color: AppColors.surfaceVariant,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Row(
+        children: [
+          Expanded(
+            flex: 2,
+            child: Text(
+              label,
+              style: Theme.of(context).textTheme.bodyMedium,
+            ),
+          ),
+          Expanded(
+            flex: 2,
+            child: Text(
+              valueA,
+              style: Theme.of(context).textTheme.bodyMedium,
+              textAlign: TextAlign.center,
+            ),
+          ),
+          const Icon(Icons.arrow_forward, size: 16, color: AppColors.textSecondary),
+          Expanded(
+            flex: 2,
+            child: Text(
+              valueB,
+              style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                    fontWeight: FontWeight.w600,
+                  ),
+              textAlign: TextAlign.center,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/lifestyle_screen.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import '../models/models.dart';
 import '../storage/local_storage.dart';
 import '../theme.dart';
+import 'about_screen.dart';
 import 'results_screen.dart';
 
 class LifestyleScreen extends StatefulWidget {
@@ -12,6 +13,8 @@ class LifestyleScreen extends StatefulWidget {
   final double sleepHours;
   final bool sleepConsistent;
   final ActivityLevel activity;
+  final bool readOnly;
+  final BehavioralInputs? initialBehaviors;
 
   const LifestyleScreen({
     super.key,
@@ -22,6 +25,8 @@ class LifestyleScreen extends StatefulWidget {
     required this.sleepHours,
     required this.sleepConsistent,
     required this.activity,
+    this.readOnly = false,
+    this.initialBehaviors,
   });
 
   @override
@@ -36,37 +41,62 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
   StressLevel _stress = StressLevel.moderate;
   DrivingExposure _driving = DrivingExposure.low;
   WorkHoursLevel _workHours = WorkHoursLevel.normal;
+  bool _useMetric = false;
 
   @override
   void initState() {
     super.initState();
-    _loadExistingBehaviors();
+    _loadInitialData();
   }
 
-  Future<void> _loadExistingBehaviors() async {
+  Future<void> _loadInitialData() async {
+    // Load unit preference
+    final useMetric = await LocalStorage.getUseMetricUnits();
+    setState(() => _useMetric = useMetric);
+
+    // If initial behaviors provided, use those
+    if (widget.initialBehaviors != null) {
+      _applyBehaviors(widget.initialBehaviors!);
+      return;
+    }
+
+    // Otherwise load from storage
     final behaviors = await LocalStorage.getBehaviors();
     if (behaviors != null) {
-      setState(() {
+      _applyBehaviors(behaviors);
-        _diet = behaviors.diet;
-        _processedFood = behaviors.processedFood;
-        _drugUse = behaviors.drugUse;
-        _social = behaviors.social;
-        _stress = behaviors.stress;
-        _driving = behaviors.driving;
-        _workHours = behaviors.workHours;
-      });
     }
   }
 
+  void _applyBehaviors(BehavioralInputs behaviors) {
+    setState(() {
+      _diet = behaviors.diet;
+      _processedFood = behaviors.processedFood;
+      _drugUse = behaviors.drugUse;
+      _social = behaviors.social;
+      _stress = behaviors.stress;
+      _driving = behaviors.driving;
+      _workHours = behaviors.workHours;
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text('Lifestyle'),
+        title: Text(widget.readOnly ? 'Lifestyle (View Only)' : 'Lifestyle'),
         leading: IconButton(
           icon: const Icon(Icons.arrow_back),
           onPressed: () => Navigator.pop(context),
         ),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
       ),
       body: SingleChildScrollView(
         padding: const EdgeInsets.all(24),
@@ -120,7 +150,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
             const SizedBox(height: 28),
 
             // Driving Exposure
-            _buildSectionLabel('Driving Exposure'),
+            _buildSectionLabel(_useMetric ? 'Driving (km/week)' : 'Driving (mi/week)'),
             const SizedBox(height: 12),
             _buildDrivingSelector(),
             const SizedBox(height: 28),
@@ -131,14 +161,15 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
             _buildWorkHoursSelector(),
             const SizedBox(height: 40),
 
-            // Calculate button
+            // Calculate button (hidden in readOnly mode)
-            SizedBox(
+            if (!widget.readOnly)
-              width: double.infinity,
+              SizedBox(
-              child: ElevatedButton(
+                width: double.infinity,
-                onPressed: _calculate,
+                child: ElevatedButton(
-                child: const Text('Calculate'),
+                  onPressed: _calculate,
+                  child: const Text('Calculate'),
+                ),
               ),
-            ),
             const SizedBox(height: 16),
           ],
         ),
@@ -169,7 +200,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (DietQuality.good, 'Good'),
         (DietQuality.excellent, 'Excellent'),
       ],
-      onChanged: (value) => setState(() => _diet = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _diet = value),
     );
   }
 
@@ -182,7 +213,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (ProcessedFoodLevel.occasional, 'Sometimes'),
         (ProcessedFoodLevel.rarely, 'Rarely'),
       ],
-      onChanged: (value) => setState(() => _processedFood = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _processedFood = value),
     );
   }
 
@@ -195,7 +226,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (DrugUse.regular, 'Regular'),
         (DrugUse.daily, 'Daily'),
       ],
-      onChanged: (value) => setState(() => _drugUse = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _drugUse = value),
     );
   }
 
@@ -208,7 +239,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (SocialConnection.moderate, 'Moderate'),
         (SocialConnection.strong, 'Strong'),
       ],
-      onChanged: (value) => setState(() => _social = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _social = value),
     );
   }
 
@@ -221,20 +252,30 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (StressLevel.high, 'High'),
         (StressLevel.chronic, 'Chronic'),
       ],
-      onChanged: (value) => setState(() => _stress = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _stress = value),
     );
   }
 
   Widget _buildDrivingSelector() {
+    // Show metric (km) or imperial (mi) based on preference
+    final options = _useMetric
+        ? [
+            (DrivingExposure.low, '<80 km'),
+            (DrivingExposure.moderate, '80-240'),
+            (DrivingExposure.high, '240-480'),
+            (DrivingExposure.veryHigh, '480+'),
+          ]
+        : [
+            (DrivingExposure.low, '<50 mi'),
+            (DrivingExposure.moderate, '50-150'),
+            (DrivingExposure.high, '150-300'),
+            (DrivingExposure.veryHigh, '300+'),
+          ];
+
     return _buildSegmentedControl<DrivingExposure>(
       value: _driving,
-      options: [
+      options: options,
-        (DrivingExposure.low, '<50 mi/wk'),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _driving = value),
-        (DrivingExposure.moderate, '50-150'),
-        (DrivingExposure.high, '150-300'),
-        (DrivingExposure.veryHigh, '300+'),
-      ],
-      onChanged: (value) => setState(() => _driving = value),
     );
   }
 
@@ -247,14 +288,14 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
         (WorkHoursLevel.high, '55-70'),
         (WorkHoursLevel.extreme, '70+'),
       ],
-      onChanged: (value) => setState(() => _workHours = value),
+      onChanged: widget.readOnly ? null : (value) => setState(() => _workHours = value),
     );
   }
 
   Widget _buildSegmentedControl<T>({
     required T value,
     required List<(T, String)> options,
-    required ValueChanged<T> onChanged,
+    required ValueChanged<T>? onChanged,
   }) {
     return Container(
       decoration: BoxDecoration(
@@ -266,7 +307,7 @@ class _LifestyleScreenState extends State<LifestyleScreen> {
           final isSelected = value == option.$1;
           return Expanded(
             child: GestureDetector(
-              onTap: () => onChanged(option.$1),
+              onTap: onChanged == null ? null : () => onChanged(option.$1),
               child: Container(
                 padding: const EdgeInsets.symmetric(vertical: 12),
                 decoration: BoxDecoration(

lib/screens/results_screen.dart

@@ -3,8 +3,10 @@ import '../models/models.dart';
 import '../risk_engine/calculator.dart';
 import '../storage/local_storage.dart';
 import '../theme.dart';
-import 'onboarding_screen.dart';
+import 'about_screen.dart';
 import 'baseline_screen.dart';
+import 'onboarding_screen.dart';
+import 'saved_runs_screen.dart';
 
 class ResultsScreen extends StatefulWidget {
   final UserProfile profile;
@@ -43,6 +45,15 @@ class _ResultsScreenState extends State<ResultsScreen> {
       appBar: AppBar(
         title: const Text('Results'),
         automaticallyImplyLeading: false,
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
       ),
       body: SafeArea(
         child: SingleChildScrollView(
@@ -107,11 +118,26 @@ class _ResultsScreenState extends State<ResultsScreen> {
               SizedBox(
                 width: double.infinity,
                 child: ElevatedButton(
+                  onPressed: _saveRun,
+                  child: const Text('Save Run'),
+                ),
+              ),
+              const SizedBox(height: 12),
+              SizedBox(
+                width: double.infinity,
+                child: OutlinedButton(
                   onPressed: _recalculate,
                   child: const Text('Recalculate'),
                 ),
               ),
               const SizedBox(height: 12),
+              Center(
+                child: TextButton(
+                  onPressed: _viewSavedRuns,
+                  child: const Text('View Saved Runs'),
+                ),
+              ),
+              const SizedBox(height: 24),
               SizedBox(
                 width: double.infinity,
                 child: OutlinedButton(
@@ -391,4 +417,55 @@ class _ResultsScreenState extends State<ResultsScreen> {
       ),
     );
   }
+
+  void _saveRun() {
+    final controller = TextEditingController();
+
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: const Text('Save Run'),
+        content: TextField(
+          controller: controller,
+          autofocus: true,
+          decoration: const InputDecoration(
+            hintText: 'Enter a label for this run',
+          ),
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Cancel'),
+          ),
+          TextButton(
+            onPressed: () async {
+              final label = controller.text.trim();
+              if (label.isNotEmpty) {
+                final navigator = Navigator.of(context);
+                final messenger = ScaffoldMessenger.of(context);
+                await LocalStorage.saveSavedRun(
+                  label: label,
+                  result: _result,
+                  profile: widget.profile,
+                  behaviors: widget.behaviors,
+                );
+                navigator.pop();
+                messenger.showSnackBar(
+                  const SnackBar(content: Text('Run saved')),
+                );
+              }
+            },
+            child: const Text('Save'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _viewSavedRuns() {
+    Navigator.push(
+      context,
+      MaterialPageRoute(builder: (_) => const SavedRunsScreen()),
+    );
+  }
 }

lib/screens/saved_run_detail_screen.dart

@@ -0,0 +1,495 @@
+import 'package:flutter/material.dart';
+import '../models/models.dart';
+import '../storage/local_storage.dart';
+import '../theme.dart';
+import 'about_screen.dart';
+import 'baseline_screen.dart';
+import 'compare_runs_screen.dart';
+
+class SavedRunDetailScreen extends StatefulWidget {
+  final SavedRun savedRun;
+
+  const SavedRunDetailScreen({super.key, required this.savedRun});
+
+  @override
+  State<SavedRunDetailScreen> createState() => _SavedRunDetailScreenState();
+}
+
+class _SavedRunDetailScreenState extends State<SavedRunDetailScreen> {
+  late SavedRun _savedRun;
+  int _savedRunsCount = 0;
+
+  @override
+  void initState() {
+    super.initState();
+    _savedRun = widget.savedRun;
+    _loadSavedRunsCount();
+  }
+
+  Future<void> _loadSavedRunsCount() async {
+    final count = await LocalStorage.getSavedRunsCount();
+    setState(() => _savedRunsCount = count);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final result = _savedRun.result;
+    final dominant = result.dominantFactor;
+    final secondary = result.secondaryFactor;
+
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Saved Run'),
+        leading: IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: () => Navigator.pop(context),
+        ),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
+      ),
+      body: SafeArea(
+        child: SingleChildScrollView(
+          padding: const EdgeInsets.all(24),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              // Label (editable)
+              _buildLabelRow(),
+              const SizedBox(height: 8),
+              Text(
+                _savedRun.displayDate,
+                style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                      color: AppColors.textSecondary,
+                    ),
+              ),
+              const SizedBox(height: 24),
+
+              if (dominant != null) ...[
+                // Dominant challenge card
+                _buildDominantCard(dominant),
+                const SizedBox(height: 24),
+
+                // Secondary factor
+                if (secondary != null) ...[
+                  Text(
+                    'Secondary Factor',
+                    style: Theme.of(context).textTheme.headlineSmall,
+                  ),
+                  const SizedBox(height: 12),
+                  _buildSecondaryCard(secondary),
+                  const SizedBox(height: 24),
+                ],
+
+                // All factors
+                if (result.rankedFactors.length > 2) ...[
+                  Text(
+                    'All Factors',
+                    style: Theme.of(context).textTheme.headlineSmall,
+                  ),
+                  const SizedBox(height: 12),
+                  ...result.rankedFactors.skip(2).map((factor) {
+                    return Padding(
+                      padding: const EdgeInsets.only(bottom: 8),
+                      child: _buildFactorRow(factor),
+                    );
+                  }),
+                  const SizedBox(height: 16),
+                ],
+              ] else ...[
+                _buildOptimalCard(),
+                const SizedBox(height: 24),
+              ],
+
+              // Profile summary
+              _buildProfileSummary(),
+              const SizedBox(height: 24),
+
+              // Model version
+              Center(
+                child: Text(
+                  'Model v${result.modelVersion}',
+                  style: Theme.of(context).textTheme.bodySmall,
+                ),
+              ),
+              const SizedBox(height: 32),
+
+              // Action buttons
+              SizedBox(
+                width: double.infinity,
+                child: ElevatedButton(
+                  onPressed: _viewInputs,
+                  child: const Text('View Inputs'),
+                ),
+              ),
+              const SizedBox(height: 12),
+              SizedBox(
+                width: double.infinity,
+                child: OutlinedButton(
+                  onPressed: _useAsStartingPoint,
+                  child: const Text('Use as Starting Point'),
+                ),
+              ),
+              if (_savedRunsCount >= 2) ...[
+                const SizedBox(height: 12),
+                SizedBox(
+                  width: double.infinity,
+                  child: OutlinedButton(
+                    onPressed: _compare,
+                    child: const Text('Compare'),
+                  ),
+                ),
+              ],
+              const SizedBox(height: 16),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildLabelRow() {
+    return Row(
+      children: [
+        Expanded(
+          child: Text(
+            _savedRun.label,
+            style: Theme.of(context).textTheme.headlineMedium,
+          ),
+        ),
+        IconButton(
+          icon: const Icon(Icons.edit_outlined, size: 20),
+          onPressed: _editLabel,
+        ),
+      ],
+    );
+  }
+
+  Widget _buildDominantCard(RankedFactor factor) {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(24),
+      decoration: BoxDecoration(
+        gradient: const LinearGradient(
+          colors: [AppColors.primary, AppColors.primaryDark],
+          begin: Alignment.topLeft,
+          end: Alignment.bottomRight,
+        ),
+        borderRadius: BorderRadius.circular(20),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          const Text(
+            'DOMINANT CHALLENGE',
+            style: TextStyle(
+              fontSize: 12,
+              fontWeight: FontWeight.w700,
+              color: Colors.white70,
+              letterSpacing: 1.2,
+            ),
+          ),
+          const SizedBox(height: 12),
+          Text(
+            factor.displayName,
+            style: const TextStyle(
+              fontSize: 28,
+              fontWeight: FontWeight.w700,
+              color: Colors.white,
+              letterSpacing: -0.5,
+            ),
+          ),
+          const SizedBox(height: 20),
+          Row(
+            children: [
+              Expanded(
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    const Text(
+                      'ESTIMATED GAIN',
+                      style: TextStyle(
+                        fontSize: 11,
+                        fontWeight: FontWeight.w600,
+                        color: Colors.white60,
+                        letterSpacing: 0.8,
+                      ),
+                    ),
+                    const SizedBox(height: 4),
+                    Text(
+                      '${factor.delta.rangeDisplay} months',
+                      style: const TextStyle(
+                        fontSize: 24,
+                        fontWeight: FontWeight.w700,
+                        color: Colors.white,
+                      ),
+                    ),
+                  ],
+                ),
+              ),
+              Container(
+                padding:
+                    const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+                decoration: BoxDecoration(
+                  color: Colors.white.withAlpha(51),
+                  borderRadius: BorderRadius.circular(8),
+                ),
+                child: Text(
+                  _getConfidenceLabel(factor.delta.confidence),
+                  style: const TextStyle(
+                    fontSize: 13,
+                    fontWeight: FontWeight.w600,
+                    color: Colors.white,
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildSecondaryCard(RankedFactor factor) {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(20),
+      decoration: BoxDecoration(
+        color: AppColors.surface,
+        borderRadius: BorderRadius.circular(16),
+        border: Border.all(color: AppColors.divider),
+      ),
+      child: Row(
+        children: [
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  factor.displayName,
+                  style: Theme.of(context).textTheme.headlineSmall,
+                ),
+                const SizedBox(height: 4),
+                Text(
+                  '${factor.delta.rangeDisplay} months',
+                  style: Theme.of(context).textTheme.bodyLarge?.copyWith(
+                        color: AppColors.primary,
+                        fontWeight: FontWeight.w600,
+                      ),
+                ),
+              ],
+            ),
+          ),
+          _buildConfidenceBadge(factor.delta.confidence),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildFactorRow(RankedFactor factor) {
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+      decoration: BoxDecoration(
+        color: AppColors.surfaceVariant,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Row(
+        mainAxisAlignment: MainAxisAlignment.spaceBetween,
+        children: [
+          Text(
+            factor.displayName,
+            style: Theme.of(context).textTheme.bodyLarge,
+          ),
+          Text(
+            '${factor.delta.rangeDisplay} mo',
+            style: Theme.of(context).textTheme.bodyLarge?.copyWith(
+                  color: AppColors.primary,
+                  fontWeight: FontWeight.w600,
+                ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildOptimalCard() {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(24),
+      decoration: BoxDecoration(
+        color: AppColors.success.withAlpha(26),
+        borderRadius: BorderRadius.circular(20),
+        border: Border.all(color: AppColors.success.withAlpha(77)),
+      ),
+      child: Column(
+        children: [
+          const Icon(
+            Icons.check_circle_outline,
+            size: 48,
+            color: AppColors.success,
+          ),
+          const SizedBox(height: 16),
+          Text(
+            'No significant factors identified',
+            style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+                  color: AppColors.success,
+                ),
+            textAlign: TextAlign.center,
+          ),
+          const SizedBox(height: 8),
+          Text(
+            'Behaviors were near optimal at this time.',
+            style: Theme.of(context).textTheme.bodyMedium,
+            textAlign: TextAlign.center,
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildProfileSummary() {
+    final profile = _savedRun.profile;
+    return Container(
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: AppColors.surfaceVariant,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Row(
+        children: [
+          const Icon(Icons.person_outline, color: AppColors.textSecondary),
+          const SizedBox(width: 12),
+          Expanded(
+            child: Text(
+              '${profile.age} years old, ${profile.sex.name}, ${profile.country}',
+              style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                    color: AppColors.textSecondary,
+                  ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildConfidenceBadge(Confidence confidence) {
+    Color color;
+    switch (confidence) {
+      case Confidence.high:
+        color = AppColors.success;
+        break;
+      case Confidence.moderate:
+        color = AppColors.warning;
+        break;
+      case Confidence.emerging:
+        color = AppColors.textTertiary;
+        break;
+    }
+
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
+      decoration: BoxDecoration(
+        color: color.withAlpha(26),
+        borderRadius: BorderRadius.circular(6),
+      ),
+      child: Text(
+        _getConfidenceLabel(confidence),
+        style: TextStyle(
+          fontSize: 12,
+          fontWeight: FontWeight.w600,
+          color: color,
+        ),
+      ),
+    );
+  }
+
+  String _getConfidenceLabel(Confidence confidence) {
+    switch (confidence) {
+      case Confidence.high:
+        return 'High';
+      case Confidence.moderate:
+        return 'Moderate';
+      case Confidence.emerging:
+        return 'Emerging';
+    }
+  }
+
+  void _editLabel() {
+    final controller = TextEditingController(text: _savedRun.label);
+
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: const Text('Edit Label'),
+        content: TextField(
+          controller: controller,
+          autofocus: true,
+          decoration: const InputDecoration(
+            hintText: 'Enter a label',
+          ),
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Cancel'),
+          ),
+          TextButton(
+            onPressed: () async {
+              final newLabel = controller.text.trim();
+              final navigator = Navigator.of(context);
+              if (newLabel.isNotEmpty) {
+                await LocalStorage.updateSavedRunLabel(_savedRun.id, newLabel);
+                setState(() {
+                  _savedRun = _savedRun.copyWith(label: newLabel);
+                });
+              }
+              navigator.pop();
+            },
+            child: const Text('Save'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _viewInputs() {
+    // Navigate to read-only baseline screen with saved data
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (_) => BaselineScreen(
+          readOnly: true,
+          initialProfile: _savedRun.profile,
+        ),
+      ),
+    );
+  }
+
+  void _useAsStartingPoint() {
+    // Navigate to editable baseline screen with saved data pre-filled
+    Navigator.pushAndRemoveUntil(
+      context,
+      MaterialPageRoute(
+        builder: (_) => BaselineScreen(
+          initialProfile: _savedRun.profile,
+        ),
+      ),
+      (route) => false,
+    );
+  }
+
+  void _compare() {
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (_) => CompareRunsScreen(initialRun: _savedRun),
+      ),
+    );
+  }
+}

lib/screens/saved_runs_screen.dart

@@ -0,0 +1,196 @@
+import 'package:flutter/material.dart';
+import '../models/models.dart';
+import '../storage/local_storage.dart';
+import '../theme.dart';
+import 'about_screen.dart';
+import 'saved_run_detail_screen.dart';
+
+class SavedRunsScreen extends StatefulWidget {
+  const SavedRunsScreen({super.key});
+
+  @override
+  State<SavedRunsScreen> createState() => _SavedRunsScreenState();
+}
+
+class _SavedRunsScreenState extends State<SavedRunsScreen> {
+  List<SavedRun> _savedRuns = [];
+  bool _loading = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _loadSavedRuns();
+  }
+
+  Future<void> _loadSavedRuns() async {
+    final runs = await LocalStorage.getSavedRuns();
+    setState(() {
+      _savedRuns = runs;
+      _loading = false;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Saved Runs'),
+        leading: IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: () => Navigator.pop(context),
+        ),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.info_outline),
+            onPressed: () => Navigator.push(
+              context,
+              MaterialPageRoute(builder: (_) => const AboutScreen()),
+            ),
+          ),
+        ],
+      ),
+      body: _loading
+          ? const Center(child: CircularProgressIndicator())
+          : _savedRuns.isEmpty
+              ? _buildEmptyState()
+              : _buildRunsList(),
+    );
+  }
+
+  Widget _buildEmptyState() {
+    return Center(
+      child: Padding(
+        padding: const EdgeInsets.all(32),
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Icon(
+              Icons.bookmark_outline,
+              size: 64,
+              color: AppColors.textSecondary.withAlpha(128),
+            ),
+            const SizedBox(height: 16),
+            Text(
+              'No saved runs yet',
+              style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                    color: AppColors.textSecondary,
+                  ),
+            ),
+            const SizedBox(height: 8),
+            Text(
+              'Save a calculation from the results screen to compare runs over time.',
+              style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                    color: AppColors.textSecondary,
+                  ),
+              textAlign: TextAlign.center,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildRunsList() {
+    return ListView.builder(
+      padding: const EdgeInsets.all(16),
+      itemCount: _savedRuns.length,
+      itemBuilder: (context, index) {
+        final run = _savedRuns[index];
+        return _buildRunCard(run);
+      },
+    );
+  }
+
+  Widget _buildRunCard(SavedRun run) {
+    return Card(
+      margin: const EdgeInsets.only(bottom: 12),
+      child: InkWell(
+        onTap: () => _openRunDetail(run),
+        borderRadius: BorderRadius.circular(12),
+        child: Padding(
+          padding: const EdgeInsets.all(16),
+          child: Row(
+            children: [
+              Expanded(
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text(
+                      run.label,
+                      style: Theme.of(context).textTheme.titleMedium,
+                    ),
+                    const SizedBox(height: 4),
+                    Text(
+                      run.displayDate,
+                      style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                            color: AppColors.textSecondary,
+                          ),
+                    ),
+                    const SizedBox(height: 8),
+                    Text(
+                      run.dominantFactorSummary,
+                      style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                            color: AppColors.primary,
+                          ),
+                    ),
+                  ],
+                ),
+              ),
+              IconButton(
+                icon: const Icon(Icons.delete_outline),
+                color: AppColors.error,
+                onPressed: () => _confirmDelete(run),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  void _openRunDetail(SavedRun run) async {
+    await Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (_) => SavedRunDetailScreen(savedRun: run),
+      ),
+    );
+    // Refresh list in case label was edited
+    _loadSavedRuns();
+  }
+
+  void _confirmDelete(SavedRun run) {
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: const Text('Delete Run?'),
+        content: Text('Delete "${run.label}"? This cannot be undone.'),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Cancel'),
+          ),
+          TextButton(
+            onPressed: () {
+              Navigator.pop(context);
+              _deleteRun(run);
+            },
+            style: TextButton.styleFrom(foregroundColor: AppColors.error),
+            child: const Text('Delete'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Future<void> _deleteRun(SavedRun run) async {
+    await LocalStorage.deleteSavedRun(run.id);
+    _loadSavedRuns();
+
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(content: Text('Run deleted')),
+      );
+    }
+  }
+}

lib/screens/screens.dart

@@ -1,6 +1,10 @@
-export 'onboarding_screen.dart';
+export 'about_screen.dart';
-export 'welcome_screen.dart';
 export 'baseline_screen.dart';
 export 'behavioral_screen.dart';
+export 'compare_runs_screen.dart';
 export 'lifestyle_screen.dart';
+export 'onboarding_screen.dart';
 export 'results_screen.dart';
+export 'saved_run_detail_screen.dart';
+export 'saved_runs_screen.dart';
+export 'welcome_screen.dart';

lib/screens/welcome_screen.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import '../theme.dart';
+import 'about_screen.dart';
 import 'baseline_screen.dart';
 
 class WelcomeScreen extends StatelessWidget {
@@ -59,7 +60,16 @@ class WelcomeScreen extends StatelessWidget {
                   child: const Text('Start'),
                 ),
               ),
-              const SizedBox(height: 32),
+              const SizedBox(height: 16),
+              // About link
+              TextButton(
+                onPressed: () => Navigator.push(
+                  context,
+                  MaterialPageRoute(builder: (_) => const AboutScreen()),
+                ),
+                child: const Text('About'),
+              ),
+              const SizedBox(height: 16),
             ],
           ),
         ),

lib/storage/local_storage.dart

@@ -1,14 +1,17 @@
 import 'dart:convert';
 import 'package:sqflite/sqflite.dart';
 import 'package:path/path.dart';
+import 'package:uuid/uuid.dart';
 import '../models/models.dart';
 
 class LocalStorage {
   static const _dbName = 'add_months.db';
   static const _tableName = 'user_data';
-  static const _version = 1;
+  static const _savedRunsTable = 'saved_runs';
+  static const _version = 2;
 
   static Database? _database;
+  static const _uuid = Uuid();
 
   static Future<Database> get database async {
     if (_database != null) return _database!;
@@ -31,6 +34,30 @@ class LocalStorage {
             updated_at INTEGER NOT NULL
           )
         ''');
+        await db.execute('''
+          CREATE TABLE $_savedRunsTable (
+            id TEXT PRIMARY KEY,
+            label TEXT NOT NULL,
+            result TEXT NOT NULL,
+            profile TEXT NOT NULL,
+            behaviors TEXT NOT NULL,
+            created_at INTEGER NOT NULL
+          )
+        ''');
+      },
+      onUpgrade: (db, oldVersion, newVersion) async {
+        if (oldVersion < 2) {
+          await db.execute('''
+            CREATE TABLE $_savedRunsTable (
+              id TEXT PRIMARY KEY,
+              label TEXT NOT NULL,
+              result TEXT NOT NULL,
+              profile TEXT NOT NULL,
+              behaviors TEXT NOT NULL,
+              created_at INTEGER NOT NULL
+            )
+          ''');
+        }
       },
     );
   }
@@ -101,10 +128,11 @@ class LocalStorage {
     return profile != null && behaviors != null;
   }
 
-  // Delete all data
+  // Delete all data (including saved runs)
   static Future<void> deleteAllData() async {
     final db = await database;
     await db.delete(_tableName);
+    await db.delete(_savedRunsTable);
   }
 
   // Get last updated timestamp
@@ -122,4 +150,124 @@ class LocalStorage {
       results.first['updated_at'] as int,
     );
   }
+
+  // ============================================
+  // Saved Runs operations
+  // ============================================
+
+  static Future<String> saveSavedRun({
+    required String label,
+    required CalculationResult result,
+    required UserProfile profile,
+    required BehavioralInputs behaviors,
+  }) async {
+    final db = await database;
+    final id = _uuid.v4();
+    final now = DateTime.now();
+
+    await db.insert(_savedRunsTable, {
+      'id': id,
+      'label': label,
+      'result': jsonEncode(result.toJson()),
+      'profile': jsonEncode(profile.toJson()),
+      'behaviors': jsonEncode(behaviors.toJson()),
+      'created_at': now.millisecondsSinceEpoch,
+    });
+
+    return id;
+  }
+
+  static Future<List<SavedRun>> getSavedRuns() async {
+    final db = await database;
+    final results = await db.query(
+      _savedRunsTable,
+      orderBy: 'created_at DESC',
+    );
+
+    return results.map((row) => SavedRun(
+      id: row['id'] as String,
+      label: row['label'] as String,
+      result: CalculationResult.fromJson(
+        jsonDecode(row['result'] as String) as Map<String, dynamic>,
+      ),
+      profile: UserProfile.fromJson(
+        jsonDecode(row['profile'] as String) as Map<String, dynamic>,
+      ),
+      behaviors: BehavioralInputs.fromJson(
+        jsonDecode(row['behaviors'] as String) as Map<String, dynamic>,
+      ),
+      createdAt: DateTime.fromMillisecondsSinceEpoch(row['created_at'] as int),
+    )).toList();
+  }
+
+  static Future<SavedRun?> getSavedRun(String id) async {
+    final db = await database;
+    final results = await db.query(
+      _savedRunsTable,
+      where: 'id = ?',
+      whereArgs: [id],
+    );
+
+    if (results.isEmpty) return null;
+
+    final row = results.first;
+    return SavedRun(
+      id: row['id'] as String,
+      label: row['label'] as String,
+      result: CalculationResult.fromJson(
+        jsonDecode(row['result'] as String) as Map<String, dynamic>,
+      ),
+      profile: UserProfile.fromJson(
+        jsonDecode(row['profile'] as String) as Map<String, dynamic>,
+      ),
+      behaviors: BehavioralInputs.fromJson(
+        jsonDecode(row['behaviors'] as String) as Map<String, dynamic>,
+      ),
+      createdAt: DateTime.fromMillisecondsSinceEpoch(row['created_at'] as int),
+    );
+  }
+
+  static Future<void> updateSavedRunLabel(String id, String newLabel) async {
+    final db = await database;
+    await db.update(
+      _savedRunsTable,
+      {'label': newLabel},
+      where: 'id = ?',
+      whereArgs: [id],
+    );
+  }
+
+  static Future<void> deleteSavedRun(String id) async {
+    final db = await database;
+    await db.delete(
+      _savedRunsTable,
+      where: 'id = ?',
+      whereArgs: [id],
+    );
+  }
+
+  static Future<void> deleteAllSavedRuns() async {
+    final db = await database;
+    await db.delete(_savedRunsTable);
+  }
+
+  static Future<int> getSavedRunsCount() async {
+    final db = await database;
+    final result = await db.rawQuery('SELECT COUNT(*) as count FROM $_savedRunsTable');
+    return result.first['count'] as int;
+  }
+
+  // ============================================
+  // Unit preference operations
+  // ============================================
+
+  static Future<void> setUseMetricUnits(bool useMetric) async {
+    await _put('useMetricUnits', {'value': useMetric});
+  }
+
+  static Future<bool> getUseMetricUnits() async {
+    final json = await _get('useMetricUnits');
+    if (json == null) return false; // Default to imperial (US)
+    return json['value'] as bool;
+  }
 }

pubspec.lock

@@ -121,6 +121,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "7.0.1"
+  fixnum:
+    dependency: transitive
+    description:
+      name: fixnum
+      sha256: b6dc7065e46c974bc7c5f143080a6764ec7a4be6da1285ececdc37be96de53be
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -525,6 +533,78 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.0"
+  url_launcher:
+    dependency: "direct main"
+    description:
+      name: url_launcher
+      sha256: f6a7e5c4835bb4e3026a04793a4199ca2d14c739ec378fdfe23fc8075d0439f8
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.2"
+  url_launcher_android:
+    dependency: transitive
+    description:
+      name: url_launcher_android
+      sha256: "767344bf3063897b5cf0db830e94f904528e6dd50a6dfaf839f0abf509009611"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.28"
+  url_launcher_ios:
+    dependency: transitive
+    description:
+      name: url_launcher_ios
+      sha256: "580fe5dfb51671ae38191d316e027f6b76272b026370708c2d898799750a02b0"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.4.1"
+  url_launcher_linux:
+    dependency: transitive
+    description:
+      name: url_launcher_linux
+      sha256: d5e14138b3bc193a0f63c10a53c94b91d399df0512b1f29b94a043db7482384a
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.2"
+  url_launcher_macos:
+    dependency: transitive
+    description:
+      name: url_launcher_macos
+      sha256: "368adf46f71ad3c21b8f06614adb38346f193f3a59ba8fe9a2fd74133070ba18"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.5"
+  url_launcher_platform_interface:
+    dependency: transitive
+    description:
+      name: url_launcher_platform_interface
+      sha256: "552f8a1e663569be95a8190206a38187b531910283c3e982193e4f2733f01029"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.2"
+  url_launcher_web:
+    dependency: transitive
+    description:
+      name: url_launcher_web
+      sha256: d0412fcf4c6b31ecfdb7762359b7206ffba3bbffd396c6d9f9c4616ece476c1f
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.2"
+  url_launcher_windows:
+    dependency: transitive
+    description:
+      name: url_launcher_windows
+      sha256: "712c70ab1b99744ff066053cbe3e80c73332b38d46e5e945c98689b2e66fc15f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.5"
+  uuid:
+    dependency: "direct main"
+    description:
+      name: uuid
+      sha256: "1fef9e8e11e2991bb773070d4656b7bd5d850967a2456cfc83cf47925ba79489"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.5.3"
   vector_math:
     dependency: transitive
     description:
@@ -541,6 +621,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "15.0.2"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: "868d88a33d8a87b18ffc05f9f030ba328ffefba92d6c127917a2ba740f9cfe4a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
   win32:
     dependency: transitive
     description:

pubspec.yaml

@@ -34,6 +34,8 @@ dependencies:
   sqflite: ^2.3.0
   path: ^1.8.3
   flutter_secure_storage: ^9.0.0
+  uuid: ^4.3.3
+  url_launcher: ^6.2.4
 
 dev_dependencies:
   flutter_test: