I've read that when selling your iphone to someone else, you should take out your sim card. But what about when you are exchanging or returning a phone to Apple? I got my iphone 5 last week but it had a nick on the side. I called Apple and they sent out another one but told me it would be weeks until I received it. They said I could use the other one in the meantime. It ended up shipping early though and I'll receive it tomorrow. Should I swap the sim cards (the brand new one for the now used one), take the sim card out of the first phone (and not swap) or just not worry about it? Thanks for the feedback.