Biometric authentication in Flutter - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is biometric authentication in mobile apps?

Biometric authentication uses unique body features like fingerprints or face to verify a user’s identity instead of passwords.

beginner

Which Flutter package is commonly used for biometric authentication?

The local_auth package helps Flutter apps access fingerprint and face recognition features.

intermediate

What is the first step before using biometric authentication in Flutter?

Check if the device supports biometrics and if the user has enrolled biometrics like fingerprint or face ID.

intermediate

Why should biometric authentication be combined with fallback options?

Because biometrics might fail or not be available, fallback like PIN or password ensures user can still access the app.

advanced

How does Flutter handle biometric authentication UI prompts?

Flutter uses native system dialogs for biometric prompts via local_auth, so UI looks familiar and secure.

Which biometric types are commonly supported on mobile devices?

A Fingerprint and Face recognition

B Voice and Retina only

C Password and PIN

D Pattern and Gesture only

Fingerprint and face recognition are the most common biometric methods on mobile devices.

What Flutter package do you use to implement biometric authentication?

A shared_preferences

B http

C local_auth

D provider

The local_auth package provides biometric authentication support in Flutter.

Before authenticating, what should your app check?

A If device supports biometrics and user has enrolled them

B If the user has internet connection

C If the app has camera permission

D If the battery is above 50%

Checking device support and enrollment ensures biometric authentication can proceed.

Why is fallback authentication important?

A Because it looks nicer

B Because biometrics can fail or be unavailable

C Because it speeds up login

D Because it uses less battery

Fallback options like PIN or password help users access the app if biometrics fail.

How does Flutter show biometric prompts to users?

A Using notifications

B Using custom Flutter widgets only

C Using web popups

D Using native system dialogs

Flutter uses native dialogs for biometric prompts to keep security and user familiarity.

Explain how to implement biometric authentication in a Flutter app.

Think about the steps from checking device to authenticating user.

Why is biometric authentication considered more secure than passwords?

Consider what makes biometrics special compared to traditional passwords.