What can you use it for, other than supported games and applications?
Well, it has a wide variaty of applications, Tobii made these 2 trackers (EyeX, a.k.a. Sentry and the new 4c) as a gaming or even consumer level peripheral while their other departments actually help people that lack motor skills to use these for a variaty of applications to replace hand control by eye control.
The consumer level trackers however have their native ingame application that are listed on their site. Some include: aim at gaze, cleanUI, infinite or extended screen, etc.
It also integrates with Windows 10 "Hello" where it can detect your face and log you in through face recognition using the IR camera.
It also has mouse warping, where you look to where you want the mouse to go, you move the mouse and the cursor jumps to your gaze.
When task switching you can highlight the screen you want to switch to and activate it by just looking at it and releasing the alt key.
Same for some menu items in windows to that you can highlight and use spacebar or enter to "click" them.
I think the full feature list should be on the Tobii website :)
So, it's not just for gaming, but also for a different way to control your computer in a way.
If you program a bit you can also use FreePIE to map custom controls to the movement of your eyes like setting it up as joystick or POV hat or whatever you want.
