Chapter 4. User Input
We've given XNA plenty of opportunity to tell us what it is thinking. Now let's even things up and let it know what's going on inside our human brains. Input is, of course, an essential part of any game and will add interactivity and excitement to our projects.
Microsoft has made some fairly strict decisions about the inputs that can be featured on Windows Phone 7 devices. All devices will have a touch screen and this will naturally form the primary input mechanism that we will use for gaming. The screens all support multitouch and are required to be able to track a minimum of four simultaneous touch points.
In terms of buttons, devices must have exactly three front-facing buttons: a Back button, a Windows button, and a Search ...