Here is Ashleigh working on her Tobii communication device. There are some apps included that help the person work on their targeting and accuracy.
On the video it shows that she has to target the person’s face on the screen with her eyes and if she does it then the person gets hit with a pie. She was doing great and really was hitting the targets quickly. You may see some lights flash at the bottom of the screen, those are the two cameras that pick up your eye movements.
My wife and I have tried this and it is not as easy as it looks. It takes a lot of concentration and focus.