SIM cards hold your contacts, call log and message information.
If your iPhone 4's SIM card breaks, you must replace it with a new card if you want to use your phone. AT&T sells SIM cards you can activate through its customer service department, then install in your phone. The only times you should replace your SIM card are when it is physically broken, or when you get constant errors while trying to view information on the phone that is stored on the SIM.
Instructions
1. Extend one side of the paperclip so it sticks out.
2. Use the open side of the paperclip to press the small indentation on the SIM card tray on the right side of the phone. The card tray will pop out.
3. Remove the SIM card from the tray and place the new one in the tray.
4. Push the tray back into the phone until it clicks in place.
Tags: card tray, side paperclip, your phone
