My touch screen doesn't always function.
My HTC Evo shift works only 1/3 of the time. The other time, the touchscreen either freezes up so I can't make choices or it will make decisions by itself, such as to open the menu and select an option. It also likes to open an options panel while I am texting someone and call them instead.
It is out of my control! I brought it in to Sprint and they said I could replace the screen for $35, but I'm not sure the screen is the problem.