Libre Contacts Backup is a FLOSS native Android app for private, local-first contact backups. No account, no cloud, no tracking — your contacts never leave your device unless you choose to move the backup file yourself.

Features:

* Lossless backup preserving the full Contact → RawContact → Data hierarchy, including contact groups

* Scheduled daily local backups at a time you choose, 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, VCF, and Excel-compatible exports

* User-controlled retention for automatic backup archives