Proximity service screen uses your device's proximity sensor to control on / off position. When you cover the sensor, the screen will be turned off when you wake up the device - full for games that need to be in the foreground, but you do not always have to watch. Flip your phone to the table, place it in your pocket, or use other means to cover proximity sensors. When the sensor unlocks, the screen returns.
This app is an open source - follow the link below for the Play Store listing for Hitachi Repo.