Z82 Reboots after short time. Have to wait for restart every hole.

Once you have started a round on the Approach Z82, by design the device will go into standby mode about 15 seconds after the Z82 is no longer being held. 

The groove under the lens (where the space in-between the thumb & pointer finder rests into) has a sensor built into curve that detects touch, and then wakes the Z82 up out of standby mode, which then turns the screen back on. 

The My Approach Z80 or Z82 Won't turn on from Sleep Mode support page available to reference as well.