How do I remove / replace the iPhone SIM card?
The SIM card or Subscriber Identity Module is a removable memory card inside your iPhone that stores information identifying the device on a cellular network. Follow these steps to remove or replace the SIM card on your iPhone:
1. Locate the SIM tray. On the original iPhone, iPhone 3G and iPhone 3GS the SIM tray is at the top of the device. On the iPhone 4 and later the Micro or Nano SIM tray is located in the center of the right side.
2. The iPhone 3G and iPhone 3GS come with a SIM removal tool. This can be used or an unfolded paper clip works just as well. All iPhones have a small hole on one side of the SIM tray. Push a paper clip end or SIM removal tool into the hole.3. The SIM tray will pop out. Remove the tray from the iPhone then remove the SIM card from the tray. When finished the SIM card and SIM tray can be reassembled and reinserted into the iPhone.