AirTriggers are the three ultrasonic sensor zones on the phone that can be customized to perform different functions, such as reproducing the actions in specific games and launching the specific apps, etc.
There are two types of AirTriggers. The first is 2-ultrasonic buttons located on the power button side of the phone, perfectly positioned for your index fingers with the phone rotated in a landscape orientation. These 2 ultrasonic buttons are used specifically for games only. The second is triggered with squeeze force along the lower part of the frame when the phone is held in portrait orientation.