Isn't this what the Kinect does to determine who you are and sign you on for the Xbox? I think that's been around for 4-5 years. Impressive they can do it all on the phone.
They bought the company Primsense that did the original Kinect in 2013, seems obvious now why.
Apple actually bought company (PrimeSense) that was responsible for Kinect sensor and it seems to work the same way. It's just impressive that they manage to fit it inside these size phone. Google tango devices are bigger.