I did something similar with KType (an iPad app to help people with speech and motor disabilities communicate better). To get out of the app's main feature - fu

I did something similar with KType (an iPad app to help people with speech and motor disabilities communicate better). To get out of the app's main feature - full-screen keyboard - you have to hold the four corners of the iPad screen at the same time. It makes sure the user does not inadvertently get out of the keyboard view.