We chose something from FRS Forbes Rehab Solutions. It was a Windows laptop in a bomb-proof enclosure and Eye Tracking software that sent IR signals to control the house appliances. Was mounted on a rolling "microphone stand" that suspended the computer in front of the patient, even in bed.
Any computer or tablet with Windows 10 with the 1709 update and a tobii eyetracker 4c has a built in text to speech app. The tobii camera costs about $200. All you need to do is download the tobii drivers to enable Eye control in accessibility options in settings. It also has a stand alone keyboard and mouse to work other programs. Scrolling function is better in windows control, another tobii program. I got windows control set up at the ALS Clinic I attend at no cost. Windows control has better scrolling, a remote control, but I like the TTS app on eye control. The tobii camera and eye control should be something you should have as a back up for when your tobii crashes, which they are want to do.
The KC VAMC provided a Surface Pro with Grid 3 as the AAC software from FRS, who refer to it as a WinSlate. I don't need an eyegaze yet so I told them not to get one yet. You never know what technology will be released tomorrow. The only issue I have with the system is that it will not integrate fully with iOS yet. Still a work in progress. It supposedly works better with Android phones.