Currently I have an iPhone 4s and my wife has my old iPhone 4. I was thinking about using her upgrade (because I used my upgrade back in March to replace her broken Android phone). How difficult would it be for me to use her upgrade but have my number put on that iPhone 5? Additionally since my iPhone 4 was out of contract when I upgraded can I have them unlock it for me? Just thought I'd ask because I'd like to sell the iPhone 4 because my wife will take the iPhone 4s. One last question, I have Applecare on my iPhone 4s, will she be able to take advantage of that should something happen to the 4s?
-We use AT&T for our service.
Thanks in advance!