The former, technically known as Hand ID, is easily the more bizarre of the two. When you hold your hand above the Z Camera to register your palm, the phone actually identifies you based on the tell-tale patterns of the veins in your hand. Pretty macabre, no? It's too bad, though, that Hand ID is really a huge pain to use correctly. The problem is, it's almost impossible to get your hand lined up just right is the first try ̵
Those AirMotion gestures are, thankfully, a little easier to live with. Here's how they work: in order to get the phone's attention, you have to make a kind of claw with your hand in front of the camera. (I'm dead serious.) From there, you can activate the shortcuts you've previously set up, play and pause your media, and even dismiss incoming calls with a swipe. To be clear, the camera can be finicky about actually seeing the claw-hand trigger correctly, and certain gestures – like turning your hand to control the phone's volume – are more gimmicky than practical. Even so, these gesture controls really work, and have come in surprisingly handy even during my limited hands-on time.