Removing the back cover of an iPhone 4 provides access to a few replaceable parts. This includes the battery, antenna and SIM card for the non-Verizon version. Be aware that removing the back cover will void your warranty. If you aren’t comfortable replacing electronic components yourself, or prefer to have your device serviced by a technician, it’s a good idea to forgo attempting to replace the iPhone’s components. Some iPhone 4 models use Philips head screws to keep the back in place. However, Apple introduced a five-point Pentalobe screw on some iPhone 4 models. You’ll need a special screw driver to remove the Pentalobe. Tips Warnings Writer Bio
