switiching owners for iPhone4 by trading SIMMs?

[CoffeeMonkey]

A couple of years ago, my mom and I bought identical iPhone4's. I've since moved to a 5, but she is still using her 4.

She upgraded to iOS7 and hates it, and while I know that Apple no longer supports downgrades to iOS6, I'm willing to trade with her.

So I was wondering if I could just take her SIMM card, put it in my old iPhone4 (which I unlocked it because it is out of contract), and switch the Apple ID to hers, and make it her phone. Is there anything I'd have to change besides SIMM cards, email accounts, and AppleID?

Thanks in advance

 

[Ann P]

No because the iphone 5 uses a nano sim card while the 4 uses a micro sim.

 

[CoffeeMonkey]

Sorry, I was unclear - I meant trade her unlocked iphone4 for my unlocked iphone4, by switching SIMM cards.

 

[dictoresno]

she can put her SIM into your unlocked phone and that phone will then "be hers". all she needs to do it load her backup onto it after you wipe it. and the way you worded your question was all messed up, thats what confused us at first.