Libre Contacts Backup

Libre Contacts Backup is a FLOSS native Android app for private, local-first contact backups. No account, no tracking, and no automatic uploads — your contacts stay on your device unless you choose to move a backup file, export data, or share a report.

Features:
• Lossless backup preserving the full Contact → RawContact → Data hierarchy, including contact groups
• SIM card phonebook captured on a best-effort basis when the device exposes it; if it cannot be read, the backup reports that it contains device contacts only. On restore, SIM contacts can be written back to the SIM card, into the device address book, or both
• Scheduled local backups at a time you choose — daily, weekly on a selected weekday, or monthly on a selected day (if a month is shorter than that day, it runs on the month's last day) — with no internet connection required
• Single-file LCB archives containing canonical JSON, VCF, CSV, and normalized exports
• Optional AES-256-GCM password-protected encryption (Android Keystore backed)
• Restore consolidates each source contact correctly, without merging different people who share a name
• Manual CSV and vCard exports, and the CSV opens in Excel and other spreadsheet apps
• Retention by age — keep the newest backups per day, week, and month with counts you choose (for example 7 daily, 4 weekly, 3 monthly), so the recent past stays densely backed up while older history thins out — or simply keep the last N sets
• Choose the app language and system, light, or dark theme from the Display menu
• Create a problem report from About and choose whether to include technical diagnostics before sharing it with an email or sharing app

Libre Contacts Backup is free and open source. If you find it useful, you can support its development — see the donation options in the project README: https://librecontactsbackup.ashkanrafiee.com/#donate