No. A SIM is a SIM. But when you switch phones you need to let your provider know this. Your acct is attched to the SIM, so no matter what phone you place it in, your acct will stay the same. But, make sure you call att and tell them the new IMEI number. If you dont it can cause instability over time. A most important of all..make sure you make it clear that you are updating you equipment and already have an account, dont activate a new account!!! Also keep in mind that whatever Ringtones,Answertones,Graphics ect that you have on your old phone will not be on the new one,and without a SD card for both phones, you cannot back them up. Make sure you save your contacts to your sim, so that you can import them to your new phone
Wrong. a sim is a sim. The only thing that identifies the two is wheather a contract or prepaid acct is active on it, if niether, than the sim is neutral.