A modern Android demonstration app showcasing offline-first architecture, two-way synchronization with Firebase Firestore, and Clean Architecture using Jetpack Compose.
Built with Room as the single source of truth, background sync via WorkManager, and conflict resolution using Last-Write-Wins strategy.
| Note List (with pending sync) | Note Editor (New) | Note Editor (Edit) |
|---|---|---|
 |
 |
 |
- Fully offline-first note creation and editing
- Realtime search by title and content
- Tag support with chips UI
- Pending sync indicator with manual sync option
- Soft delete with two-way sync (local + Firebase)
- Automatic background sync using WorkManager
- Last-Write-Wins conflict resolution for multi-device support
- Initial pull from Firebase when local database is empty
Room acts as the single source of truth.
UI (Compose)
↓
ViewModel
↓
RepositoryImpl
├── Local (Room) ← Single Source of Truth
└── Remote (Firestore) ← Background sync
- Kotlin + Jetpack Compose
- Clean Architecture
- MVVM + StateFlow
- Room Database (Single Source of Truth)
- Firebase Firestore
- WorkManager + Constraints
- Hilt (Dependency Injection)
- Navigation Compose + Hilt Navigation
- Kotlin Coroutines + Flow
data
├─ local (Room)
├─ remote (Firestore)
├─ repository
└─ sync (WorkManager)
domain
├─ model
├─ repository (interface)
└─ (No UseCase - kept simple for demo)
presentation
├─ navigation
├─ notes (List + Editor)
└─ theme
Luong Ho
Android Developer