Integrating Biometric Authentication

Showing an ID card to a receptionist is a good comparison for a fingerprint check. The receptionist looks at the card, hands it back, and tells the office only "yes" or "no". The office never sees or keeps the card. Biometric authentication works the same way: the phone's secure hardware compares your fingerprint or face with what it stored during setup, and your app receives only the answer.

Your app therefore never handles biometric data, and you do not store or compare any. Your job is to ask the system for a check and to act on the result