So aside from the generally unavoidable tiny scratches on the back and scuff/spots on the antenna rim, I take really good care in making sure my iPhone stays solid and intact. I had an otterbox on it for several months after going caseless carefully for about a month, and I recently took the case off. I don't throw my phone or drop it without the case on, although when I had the case there were instances in which my phone fell, usually on a softer surface such as carpet or heavy grass, but I've not had any drop without the case before. I was holding my phone and I noticed that the back was making a sticky noise when I pushed down on it, as if it was popping up. I looked and felt and it seemed flush, and after pushing down lightly through the back, the sticky noise is now gone. The sticky noise was around the bottom of the device, as far up as the "iPhone" words down to the base of the device. Is this a major issue to worry about? Should I be concerned that my back glass could be coming up? Should I maybe make an Apple appointment about my phone?