I just turned my 3GS on a couple of weeks after getting my 4S and noticed a distorted spot in the middle of the screen which I assumed to be a mark on the screen cover. After removing the cover the mark was still there and when I open something with a white background the mark makes the area dark grey. I also noticed that the top left corner was lifted up slightly and part of the rubber seal had come off. When I apply really light pressure anywhere on the screen or the home button the screen distorts/blurs like when you press an LCD screen with some force. This definitely isn't because of the pressure, applying the same pressure on my 4S does not cause this problem and I never had this until now. I haven't dropped the phone or anything, it's been out of battery in the same position for two weeks. I can't think of any reason for this to happen. I've tried removing and putting the screen back on but the top left corner still doesn't stay in the correct position. When I remove the screen the smudge mark in the middle of the screen goes but reappears when screwed back in place. Another thing I noticed is that the phone doesn't fit in the case properly which I've had it in for over a year. It's almost like the plastic has warped and bent causing the screen to bend. I can't take it to an Apple store as it's obviously out of warranty. Has anyone else had this problem? All of the threads I've seen where people had similar problems got replacements as they still had warranty.