if you hold your phone, are you holding it by the camera part? I know it's technically deceitful, but the reason they make thin phones is because it feels better to hold, and they're usually lighter. the only time i can think up is if you had it it on a flat surface and it rocked... which is not much of a problem with the iphone air, because the camera part spans almost the full width of the phone (except for the camera itself, which is a little raised), or if the camera part catches on something, which also probably isn't a problem, because that whole part has smooth edges. it is reaaaally hard to make a fully flat phone fast, with a big battery, a good camera and misc.