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With the original and 3G I skinned mine with a BestSkinsEver skin and was set to do that with the iP4. And for a little while I did use it naked - almost - with a gelaskins covering the back and sides. But I dropped it and was really lucky it landed on grass. The edges of the glass aren't protected by any bezel and will chip easily if dropped. I don't use anything on the glass. But I have found that a case isn't a bad way to go and I like the feel.

I was using a bumper and since I wanted to run with it, I upgrade to the Marware Sportshell Convertible. Very nice case. Got it off Amazon for $19. It has 2 backs, one that has a clip for making a video/FaceTime stand and clipping onto the running/workout band. The other is flat. It is very easy to switch out the backs, so I use it without the clip most of the time. I still have my Gelaskin on the phone, which has a cool picture on it, so I am going to get the Marware Custom Shell that has the clear back. I'm sure it will scratch, but I can see the skin, and switch out to the black with clip for running. I am really happy with this case.
 
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