Official Description: The Biometric library is a static library that you can add to your Android application. It invokes BiometricPrompt on devices running P and greater, and on older devices will show a compat dialog. Compatible on devices running API 14 or later.

CommonsWare’s Notes

This artifact supplies its own implementation of BiometricPrompt for collecting a Fingerprint or other form of biometrics from the user. On Android 9.0 and higher, it serves as a wrapper around the framework implementation of BiometricFragment. On older devices, it shows its own UI.