iPhone 3g to iPhone 4 upgrade SIM question

Discussion in 'iPhone Tips, Help and Troubleshooting' started by jamesnsw, Sep 14, 2010.

  1. jamesnsw macrumors newbie

    Joined:
    Nov 5, 2009
    #1
    I'm thinking of buying a friend's extra iPhone 4 to replace my iPhone 3g. Will I be able to just pop my SIM card in and use the iPhone 4? Or is there a different kind of SIM card?

    Is there anything else I need to think of before buying his phone, and selling mine?
     
  2. Carlanga macrumors 604

    Carlanga

    Joined:
    Nov 5, 2009
    #2
    is a microsim now, so you would need to either cut your old SIM or ask AT&T for a new microsim w/ your phone number...
     
  3. jamesnsw thread starter macrumors newbie

    Joined:
    Nov 5, 2009
    #3
    Would AT&T do that for me?
     
  4. Carlanga macrumors 604

    Carlanga

    Joined:
    Nov 5, 2009
    #4
    yeah, you just go and ask them to transfer your number from your old SIM to new microsim card since you bought an iPhone 4.... Once you do that, only the microsim (w/ your same number) is going to be working and your older sim gets deactivated by them.

    You can buy also a microsim adapter if you ever want to use the microsim in another phone w/ regular sim card size also!
     
  5. jamesnsw thread starter macrumors newbie

    Joined:
    Nov 5, 2009
  6. Carlanga macrumors 604

    Carlanga

    Joined:
    Nov 5, 2009
    #6
    No prob.! This works only if you are both owners of iPhones bought from AT&T or US Apple Store, if the friend bought it from someplace else you might need to jb and unlock it. If both of you bought them from AT&T then you should have no problems besides just changing to a microsim card! Also, if you would want to jb the iPhone 4 the newest jb might not be untethered and the unlock is an unkwon for know for 4.1, if you don't care for jb or unlock then you would be good to go w/ the simple sim card size change!

    Also just remember, make sure the iPhone 4 was activated the first time w/ the original owners zip & last 4 of the SSN so that you can actually use your sim card on it or else you might not be able to activate it or tell him to input them for you for the first time activation.
     

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