Your phone isn't always in your hand. In fact, your phone isn't in your hand for the vast majority of the day most likely. And it's in those scenarios that some

Your phone isn't always in your hand. In fact, your phone isn't in your hand for the vast majority of the day most likely. And it's in those scenarios that something like this could be cool if it works well. If it can detect your presence before you actually pick it up it could do things like fire up the face auth systems to give quicker unlock. It can auto-lock if you set it down and walk away without manually turning it off or waiting for the timeout. If the alarm is going off it can lower the volume if it detects your presence before you actually dismiss or snooze the alarm. There's all sorts of possibilities for all the times where you are not holding your phone. If it works well, that is.