If your device has biometric authentication (allowing you to use your fingerprint or face to unlock your phone and log in to apps) set up when you first register the mobile app, you’ll be automatically asked if you'd like to use it to log in.
If your app is already registered, you can enable biometrics anytime by going to:
- Android: Settings > Biometric login
- iOS: Settings > Touch ID or Face ID
To turn biometrics off, simply go back to the same setting and toggle it off.