Mobile Offline Support
Table of Contents
Overview
Design offline-first mobile applications that provide seamless user experience regardless of connectivity.
When to Use
- Building apps that work without internet connection
- Implementing seamless sync when connectivity returns
- Handling data conflicts between device and server
- Reducing server load with intelligent caching
- Improving app responsiveness with local storage
Quick Start
Minimal working example:
import AsyncStorage from '@react-native-async-storage/async-storage';
import NetInfo from '@react-native-community/netinfo';
class StorageManager {
static async saveItems(items) {
try {
await AsyncStorage.setItem(
'items_cache',
JSON.stringify({ data: items, timestamp: Date.now() })
);
} catch (error) {
console.error('Failed to save items:', error);
}
}
static async getItems() {
try {
const data = await AsyncStorage.getItem('items_cache');
return data ? JSON.parse(data) : null;
} catch (error) {
console.error('Failed to retrieve items:', error);
return null;
}
}
// ... (see reference guides for full implementation)Reference Guides
Detailed implementations in the references/ directory:
| Guide | Contents |
|---|---|
| React Native Offline Storage | React Native Offline Storage |
| iOS Core Data Implementation | iOS Core Data Implementation |
| Android Room Database | Android Room Database |
Best Practices
✅ DO
- Implement robust local storage
- Use automatic sync when online
- Provide visual feedback for offline status
- Queue actions for later sync
- Handle conflicts gracefully
- Cache frequently accessed data
- Implement proper error recovery
- Test offline scenarios thoroughly
- Use compression for large data
- Monitor storage usage
❌ DON'T
- Assume constant connectivity
- Sync large files frequently
- Ignore storage limitations
- Force unnecessary syncing
- Lose data on offline mode
- Store sensitive data unencrypted
- Accumulate infinite queue items
- Ignore sync failures silently
- Sync in tight loops
- Deploy without offline testing