This is a black screen for set-top box when you don't want to see anything on the screen such when you sleep however you don't want to turn off your set-top box and TV to keep some application running.

No ADS
No Internet connection required
No information collect from devices
Smallest size in the play store (Only ~ 7000 Bytes)
Compatible since Android 1.0

MUST-HAVE for all Set-top box.