This is my second iPhone 4S that I have gotten and put on the ios 7 updates. On both the devices the back camera does not work. The app comes up black. Sometimes I can switch to use the front camera, but not always. Verizon is sending me a third phone because Apple keeps saying it is a hardware issue. However the camera worked just fine in the old ios. Leads me to believe its a software issue. I've tried resets, network resets changing options soft resets, everything I've found online. The camera won't work. Please help.