Replacing the rear camera in your GSM or CDMA iPhone 4 is an easy Do-It-Yourself (DIY) repair, as long as you have the right tools and parts. We will show you a demonstration and explain the procedure to do that step by step. The camera of your iPhone will start working again. Even though, the GSM and CDMA variants are slightly different, this procedure will work for both. So follow this procedure to replace the camera of your iPhone 4.