Developer utility: Detects whether your Android device has hardware face detection available on any of the cameras. Note that Android 4 and higher has face detection supported in the API, but not all devices support this. Displays a message on the main screen indicating how many faces can be detected per camera. This is useful for developers who wish to see if a device has hardware face detection before purchasing it. Note: this is face detection, not face matching. That's a whole different ballpark's radar screen.