If the auto-brightness is turned on, the brightness of the screen will dim when you play games in landscape mode because your hand is blocking the sensor. When you turn on [Lock brightness], the brightness of screen will be locked at its current brightness, and will not dim during the gameplay.
To turn it on/off:
1. When you launch a game, swipe from right edge (landscape mode) or from bottom (portrait mode) to bring out the navigation bar.
2. Tap the [Game Genie] icon.
3. Toggle the [Lock brightness] button to turn it on/off.
