Complete Backup Guide Before Flashing Custom ROM
Golden Rule: Always backup before you flash. There's no such thing as too many backups.
Why Backup is Critical
Flashing a custom ROM typically requires a factory reset, which means:
- All apps deleted
- All app data gone
- Photos and videos erased (if on internal storage)
- Messages and call logs lost
- 2FA apps reset (Google Authenticator, etc.)
Quick Backup Checklist
- NANDroid backup (full system image)
- Photos & videos synced to cloud
- Contacts synced to Google
- Messages backed up
- 2FA codes exported
- App data backed up
- WhatsApp/Telegram backed up
- Important files copied to PC
1. NANDroid Backup (Full System Image)
A NANDroid backup is a complete snapshot of your entire device that can be restored.
Create NANDroid in TWRP
1. Boot into TWRP recovery
2. Tap "Backup"
3. Select partitions:
- Boot ✓
- System ✓
- Data ✓
- Vendor ✓ (if available)
4. Swipe to backup
5. Wait for completion
Backup Location
Backups are stored in:
/sdcard/TWRP/BACKUPS/[device-serial]/
Copy to PC
Critical: Copy the backup folder to your PC!
adb pull /sdcard/TWRP/BACKUPS ./
2. Cloud Sync (Google Account)
Enable Sync
Settings → Accounts → Google → [Your Account]
Enable sync for:
- Contacts ✓
- Calendar ✓
- App data ✓
- Chrome ✓
Verify Sync
Visit contacts.google.com to confirm contacts are synced.
3. Photos & Videos
Option 1: Google Photos
1. Open Google Photos
2. Tap profile → Photos settings
3. Enable "Backup & sync"
4. Wait for complete upload
Option 2: Transfer to PC
# Connect phone via USB
# Enable File Transfer mode
# Copy DCIM folder to PC
4. Messages Backup
SMS Backup & Restore App
- Install SMS Backup & Restore
- Tap "Back Up Now"
- Save to Google Drive or local storage
- Transfer backup file to PC
1. Open WhatsApp → Settings → Chats
2. Chat backup → Back up to Google Drive
3. Wait for backup to complete
Telegram
Telegram syncs to cloud automatically. Just ensure you're logged in.
5. 2FA/Authenticator Apps ⚠️
This is the most critical step! Losing 2FA access can lock you out of accounts.
Google Authenticator
- Open Google Authenticator
- Tap menu → Transfer accounts
- Export accounts (shows QR code)
- Screenshot the QR code or scan with another device
Authy (Recommended for Future)
Authy syncs to cloud - consider switching!
Microsoft Authenticator
Enable cloud backup in settings.
Manual: Save Backup Codes
For each important account:
- Go to security settings
- Download backup codes
- Save to secure location
6. App Data Backup
With Root (Best)
Titanium Backup or Swift Backup:
- Install from Play Store
- Grant root access
- Backup all apps + data
- Save backup folder to PC
Without Root
Google Backup:
Settings → System → Backup → Back up to Google Drive
Note: Not all apps support this method.
App-Specific Backups
| App | Backup Method |
|---|---|
| Settings → Chats → Chat backup | |
| Telegram | Cloud sync (automatic) |
| Signal | Settings → Chats → Chat backups |
| Games | Usually account-based |
| Password Managers | Export vault to file |
7. Files & Documents
Copy to PC
# All internal storage
adb pull /sdcard/ ./phone_backup/
# Or use USB File Transfer
Selective Backup
Important folders:
/Download//Documents//DCIM//Pictures/- Any app-specific folders
8. Device-Specific Data
WiFi Networks
# With root, backup wifi config
adb pull /data/misc/wifi/WifiConfigStore.xml ./
Ringtones & Notifications
Copy from:
/sdcard/Ringtones/
/sdcard/Notifications/
Backup Verification Checklist
Before flashing, verify all backups:
✅ NANDroid backup created AND copied to PC ✅ Google sync shows recent activity ✅ Photos app shows "Backup complete" ✅ SMS backup file exists ✅ 2FA codes exported/screenshotted ✅ WhatsApp backup to Google Drive complete ✅ Important files copied to PC
Restore After Flashing
NANDroid Restore (Full)
1. Boot into TWRP
2. Tap "Restore"
3. Select backup
4. Select partitions to restore
5. Swipe to restore
Selective Restore
After setting up new ROM:
- Sign in to Google account (restores contacts, calendar)
- Open Google Photos (photos sync back)
- Restore SMS from backup
- Re-setup 2FA apps using backup codes
- Reinstall apps from Play Store
Pro Tips
💡 Use Multiple Backup Locations
- Local (PC/external drive)
- Cloud (Google Drive, OneDrive)
- Another device
💡 Regular Backups
Create a schedule:
- Weekly: NANDroid backup
- Daily: Cloud sync enabled
- Before any flash: Full backup
💡 Test Your Backups
Occasionally verify that backup files are accessible and not corrupted.
Common Mistakes to Avoid
❌ Only backing up to the phone (wiped during flash) ❌ Forgetting about 2FA apps ❌ Not verifying backup completion ❌ Trusting "I'll remember my passwords"
Remember: The 10 minutes you spend backing up can save you days of recovery!
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