This is an interesting situation. A number of iPhone 4 devices are dropping the signal when consumers hold the phone in their hands. It’s unclear why that is the case, but it appears to be a relatively prominent problem. Apple hasn’t officially commented on the problem; however, some users believe it’s just a display issue and the signal is fine. Others note that when the bars disappears, the device drops ongoing calls. Only Apple devices would have problems like these. We suppose this comes with pushing the envelope with innovation.