Usually, Android provides a number of procedures to unlock your phone. But now we have a new way to unlock phone with face. Usually, when we are using our device, then anybody can see our pattern, PIN, or password. But in this feature, when it does not recognize your entire face, it will not unlock your device. Here is how to use face recognition in your device.
Please read the originial post here: https://camcafee.com/how-to-use-face-recognition-in-android/