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jent

macrumors 6502a
Original poster
Mar 31, 2010
918
763
My brother broke the screen to his iPhone 3GS so I gave him my old iPhone 4. I've done this manual upgrade several times myself, but I wanted to write it out and see what the MacRumors Forums community thought, just to double-check my instructions and make sure they're readable to a regular non-techie.

1. Get both iPhone 3GS and iPhone 4 in hand.

2. Restore iPhone 4 to factory settings if necessary.

3. Plug iPhone 3GS into computer and back up via iTunes.

4. Go to Settings -> General -> About and note the IMEI if the SIM card in the iPhone 3GS.

5. Note the IMEI number of the new, unused micro-SIM that will be used going forward with the iPhone 4.

6. Call your service provider and tell them the cell phone number you wish to upgrade, confirm the IMEI of SIM card in your 3GS and read off the IMEI of the new micro-SIM card that you want them to transfer service to. They will deactivate the iPhone 3GS SIM card and activate the iPhone 4 micro-SIM.

7. Restart your iPhone 4 and confirm it gets service. Make a call, send a text, and use mobile data to make sure everything is in order.

8. If desired, restore the iPhone 3GS to factory settings. Keep the old, deactivated SIM card for activation purposes when you reset or restore the 3GS via iTunes.

Thanks for any corrections or suggestions!
 
Why so complicated? All you need to do is back up info and then switch sims/call phone company

Different iPhones use different sizes of SIM cards.

The original iPhone, 3G, and 3GS use a regular SIM card, the 4 and 4S use a micro-SIM, and the 5 uses a mini-SIM.

Switching from one size to another requires cutting the SIM card down, using a little plastic adapter (if you move from a bigger to a smaller size, and smaller to a bigger size, respectively), or just simply calling your service provider an having them map your cell phone service to the new SIM card.
 
Yes I know what you're saying. You're just making it so sound so difficult. :eek: Every time I've upgraded my phone, from the 3G to the 5, I just cut down my sim from an online template or go get a free one from my carrier store. It is no big deal.
 
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Yes I know what you're saying. You're just making it so sound so difficult. :eek: Every time I've upgraded my phone, from the 3G to the 5, I just cut down my sim from an online template or go get a free one from my carrier store. It is no big deal.
Yup, as you and I are techies. I'm just trying to make this as clear as possible for my non-techie brother.

Also, most people upgrade phones only when they re-up their contract, meaning the old SIM gets deactivated automatically and the SIM that already comes inside the new iPhone gets automatically activated, so it's only a subset of smartphone users that would ever have to deal with this kind of thing.
 
1. Take both phones in to your carrier
2. Tell them what you want(swapping phones)
3. Walk out with a working iPhone 4

The reason I suggest this is because it sounds like your brother is not tech savvy. This should be the easiest thing for him to follow unless he is in the middle of nowhere.
 
yep go the shop for a sim and they will sort, when i sold my ip4 the new owner had to go to the shop as his sim was so old it couldn't be cut down, the shop sorted it all
 
yep go the shop for a sim and they will sort, when i sold my ip4 the new owner had to go to the shop as his sim was so old it couldn't be cut down, the shop sorted it all


When you say 'shop' are you referring to the MAC store (Apple) or to the Cellphone/Internet store (Rogers)?
 
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