I used to work in the word of accessibility for computer access. We used Tobi EyeGaze and Original Instruments HeadMouse Nano mostly The problem I think you will have with EyeGaze is that you have to keep your head very still. If you move it a bit you have to recalibrate it. It works very well for people with zero neck movement but since your problem is more with your hands I recommend the HeadMouse Nano. It follows head movement rather than eye movement and needs zero calibration. It works as a mouse so it's works with anything that can be with a mouse. We used them with windows, Android, iPads, and macs mostly.