Just came onto the boards looking for iPhone 4 heat related issues and voila...found a few. Had mine since launch day and yes, the signal bars drop when I hold it in that 'special' way, but no calls dropped and otherwise the phone's been great. Just a while ago, I 'closed' down a bunch of apps from the multitasking tray just before getting a phone call. After about two minutes on the phone, the left rear and side of the phone (when looking at the back) got hot to the point of being really uncomfortable to hold!! Hung up with the call....and within about 3-5min it was cool/normal to the touch. Received another call minutes later and it started to do the same thing after about two or three minutes of talking!! It is definitely heating up beyond comfort on the left side (battery side?) when you're looking at the back of the phone...battery capacity was at 29% when this issue started, but can't believe that should be a factor. Haven't gotten any overheat warnings. Anyone else starting to get these issues or anything similar?? device FYI--I only have about 15-20 apps on the phone and have only used appx 6hrs total talk time since purchase...have been treating it almost delicately anyway since it's my first iPhone, but this is concerning!!