In point of fact this fresh feature is called «panic detection mode», and it's some distance a system of Android 7.1 that helps customers to exit malicious applications rapidly. (androidnougatupdate.info)
In fact, there are 5 different detection modes to choose from. (geekwrapped.com)
If you want to use the rear shooter for your selfies, a face detection mode helps achieve that, though focal width is definitely narrower. (androidauthority.com)