Two Factor Authentication - Bitwarden Authenticator

Bitwarden Authenticator is a free and open source multi factor authenticator for Android and iOS supporting Time-based one-time password (TOTP) standard algorithm with a locally encrypted vault using AES-256 protected by a password or biometrics (face or fingerprint unlock) using Keychain on iOS and Keystore on Android. Despite being a standalone application it provides seamless integration with its homonymous password manager. New entries are added using QR code, entered manually or imported from other applications. With its data easily backed up or exported in several formats.