Wear Locker

This app creates a system overlay on the screen when it is turned on that intercepts touch events, preventing the user from accidentally opening an app when the watch is being used. It unlocks once the chosen gesture is input, such as double tap, press and hold, or swipe. There are also options for the watch to vibrate once unlocked and to customize the color of the overlay.

Github: https://goo.gl/3e6TEW