Mobile Engineering Tools
Biometric Auth Reference
Search biometric authentication concepts for iOS and Android. Covers LocalAuthentication, BiometricPrompt, Keychain access control, and enrollment change handling.
No data is transmitted — everything runs locallyTool
About this tool
Biometric Auth Reference
The Biometric Auth Reference covers iOS LocalAuthentication, Android BiometricPrompt, Keychain and Keystore key protection, and enrollment change invalidation handling.
• Look up LocalAuthentication API before implementing Face ID support
• Reference BiometricPrompt class levels before choosing strong vs weak biometric
• Find Keychain access control attributes for a biometric-protected key
• Handle biometric enrollment change that invalidates stored keys
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FAQ
What does this tool tell you?
The Biometric Auth Reference covers iOS LocalAuthentication, Android BiometricPrompt, Keychain and Keystore key protection, and enrollment change invalidation handling.
What affects the result most?
iOS LocalAuthentication: LAContext.evaluatePolicy — deviceOwnerAuthenticationWithBiometrics. Keychain with kSecAttrAccessibleWhenUnlocked: key only accessible when device unlocked — use for sensitive ops. Face ID vs Touch ID fallback: use LABiometryType to detect and adjust UX — don't assume Touch ID.
How should I use the result?
Use this tool to orient quickly to the concepts, field names, or values you are about to look up in a full specification or vendor documentation. It summarizes the common cases; the authoritative source remains whichever standard or vendor doc defines the values themselves.