I updated my iPhone 4 with iOS 4.3.3 last night and ever since, none of my apps open. When I select an app, the screen goes black for about a half a second, then goes right back to the window I was on. I have no idea why this is going on or how to fix it. Do I need to roll back the version of iOS software? If so, how do I go about doing it? Any help would be greatly appreciated...thanks!