Built Around Your Privacy: Citadel Auth 1.0 Is Now Live

When we introduced Citadel Auth earlier this year, we described it as the offline-first 2FA app we built because we couldn't find one we trusted. Version 1.0.0 is now live on Google Play and it's everything that phrase requires to be true.

The core principle remains unchanged: your 2FA secrets are in a SQLCipher-encrypted vault on your device. Screenshots and screen recording are blocked. App content is hidden in the recent-apps switcher. On Android, the INTERNET permission is removed at the build level, making the app structurally incapable of initiating a network request. On iOS, the only network path is fetching a token's service icon by domain name.

Every action such as deleting a token or exporting it requires your master password. If you need to start completely fresh, the full vault deletion in Settings is permanent and password-gated with no recovery path, deepening the security layer.

The organization layer remains one of the features we're most proud of. Profiles let you maintain distinct credential contexts each with its own Groups for granular categorization, removing the clutter most authenticators get at scale. Tokens can be pinned, tagged, and searched across all profiles simultaneously. The Personal theme system lets you fully customize the app's appearance with your own background, text, and accent colors, with changes applied live across the interface.

Citadel Auth supports TOTP (RFC 6238) and HOTP (RFC 4226) with SHA-1, SHA-256, and SHA-512 algorithm selection, 6, 7, or 8-digit codes, and 30s, 60s, or 90s periods. Tokens can be added by QR scan, manual entry, or URI import. Migration from Aegis, 2FAS, and Ente Auth is supported. Encrypted backups use Argon2id (64MB, 3 iterations) with AES-256-GCM, a separate encryption layer for data leaving the device.

It's free and contains no ads. Download it on Google Play.

Or explore the source on GitHub.