How to identify fingerprint based user in Android M release?

Question

Can I use the FingerprintManager in Android M (API 22) to identify (along with authorization) the user?

For example, there are two fingerprints registered on the device, one for user A and one for user B. Does the API provide support for detecting which user, A or B, has just logged in?

Answer 1

Not. In fact, the definition of Android compatibility for Android 6.0 is indicated in the Fingerprint section (7.3.10):

SHOULD NOT allow third-party applications to distinguish between individual fingerprints.

Therefore, if you can write an application that uses a fingerprint as a user authentication mechanism, you can use any registered fingerprint associated with the current user account.

The Fingerprint method for Android does not contain a fingerprint name or any unique identifier. he processed every registered fingerprint in the same way and just authenticated only. (valid user or invalid user he is)

Fingerprint storage attached to the device (from the Nexus FAQ):

Fingerprint data is stored securely and never leaves your device. Your data does not apply to Google or to any applications on your device.

Therefore, there is no way for an application to access fingerprint data in order to be able to save it or use it on all devices.

Suggestion : To distinguish between multiple users or devices, you should use an external fingerprint scanner. There are some external fingerprint scanners compatible with the Android Platform and the Android SDK. These SDKs allow you to register and verify multiple users.