It would appear that the oleophobic coating that covers the screen of my 3GS has worn away. Some backstory: I take exceptional care of my iPhone- it still looks as it did on the day I bought it (except for the screen) I don't allow anything besides cloth (or my finger ) to touch the screen When it is in my pocket, nothing else is in there with it I only wipe the screen with a microfiber cloth or a soft t-shirt I have a case, but no screen protector Since I would say that I use my iPhone no differently than anyone else, and that I have not read about any similar complaints by other users, I believe that the only explanation is that my screen is defective. Perhaps the coating didn't set properly (or something like that). I have an appointment at the Apple Store tomorrow, so hopefully they'll replace my iPhone. It's a shame, because other than that, it works perfectly- no light leaks, the battery is good, everything is flush, etc. However, I have noticed over the past couple of months that the smudge area getting larger, and I figure that I should nip this in the bud before it gets even worse. Below are two photos. The reason I'm displaying two photos is to show that the smudge area is consistent before and after a clean wipe of the screen. To bring out the entire smudge area, I rub my finger back-and-forth horizontally across the entire screen. Obviously, with normal use, I wouldn't do that, but that area would normally slowly appear as I use the iPhone. I cleaned the screen with a microfiber cloth after photo 1, and then rubbed my finger on the screen again to bring out the smudge area right before I took photo 2. As you can see, the smudge area is the same shape in both photos. I can repeat this over and over with the same results. It is very distracting, especially when I use my iPhone outside. And living in California, I'm outside quite a bit. Anyone else notice anything like this with your 3GS?