i think the issue some people may be noticing are wear marks that over a year or two could theoretically occur with very slight movement where the case meets the phone. the inner polycarbonite shell touches the phone around the outer part of the screen. even in a super tight case a phone may move ever so slightly within the case and over time that might cause rub marks in the glass. not really indentations in the glass, just rub marks that may appear cloudy. just a thought.
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was this all over the screen or just in the corners where the case meets the glass? not sure if the case for the 4 is designed differently. never used one for my 4.
It was just near the top of the screen, I assume where it received a lot of pressure. Note that I had removed the built-in screen protector from the defender, and used a regular/plastic screen protector.