The KnockON feature allows you to double-tap the screen to easily turn the screen on or off. You can disable this feature in the Display settings. For the best results, keep the tablet still when using KnockON.
- Quickly double-tap the center of the screen to turn the screen on.
- Quickly double-tap the Status Bar, an empty area on the Home screen, or the Lock screen to turn the screen off.
NOTE
The KnockON feature can be turned off in the Display settings
menu. From the Home screen, tap Apps 
(in the Quick
Access Bar) > Settings 
> Display > KnockON > tap the KnockON checkbox 
.