Subscriber Identity Module or SIM cards are microchips inserted into cell phones on some networks, including AT&T. A SIM card not only identifies your phone to the mobile network, but sometimes saves information, such as contact phone numbers. While the iPhone does not save its contact information to a SIM, it is able to import and then display the information previously saved to a SIM from another phone. Importing SIM contacts from your last phone to the iPhone means that you won’t have to manually enter each contact. Tips Writer Bio
