I've had my iPhone 4 for over a year now, but have recently been having problems with it freezing. It's always after a call (incoming or outgoing). Sometimes it won't even end the call by touching "End Call" and I have to hit the button on the top of the phone (I forget exactly what it's called) to get the call to end. The touch screen just totally freezes. It's usually only for a short time (a minute or so), but that can seem like forever if you're trying to do something. Turning the phone on and off (again, with the top button) doesn't help... I still have to wait for it to start working again. I've powered the phone completely off and that doesn't seem to do anything. I think this all started after the latest IOS update. Are others having this problem? Any ideas on why this is happening? Any suggestions on how to fix it? Thanks!!!!!!!