How does the Watch know when you cover it with your hand?

[DavidTheExpert]

One of the features is that if you're getting an incoming phone call you can mute it by covering the watch face with your hand. How does it know? As far as I'm aware, it doesn't have any proximity sensor like the iPhone does... does it?

 

[Vegasryn]

It does have a ambient light sensor which would detect the dramatic light change.

 

[Che Castro]

You have to touch the watch face with your hand
Not hover over it

 

[DavidTheExpert]

You have to touch the watch face with your hand
Not hover over it

But how does it distinguish that from a single touch? Is it using the multitouch or some sort of light sensor like the other user said?

 

[roblognick]

it's probably both the fact that the light sensor goes dark and the watch face feels your palm on a couple of points.