# 27. Implement iOS settings/preferences store

meta:
  id: native-business-logic-migration-27
  feature: native-business-logic-migration
  priority: P1
  depends_on: [native-business-logic-migration-15]
  tags: [implementation, ios, settings]

objective:
- Implement settings store using UserDefaults and App Group

deliverables:
- SettingsStore.swift
- AppSettings.swift
- ReadingPreferences.swift
- NotificationPreferences.swift
- Settings migration

tests:
- Unit: Test property storage/retrieval
- Unit: Test defaults
- Unit: Test synchronization

acceptance_criteria:
- All settings persisted
- Defaults properly set
- Changes observed in real-time
- App Group sync working
- Settings migrated between versions

validation:
- Run unit tests
- Test with Xcode preferences inspector

notes:
- Use UserDefaults for simple settings
- Use App Group for shared settings
- Observe changes with notifications
