Ok I have read forums where it is possible to use your iPhone 4 on a prepaid plan with separate data. I know AT&T does not give u a micro sim card so I would have to trim it myself. But I have one slightly confusing question. When I go to to buy the sim card at an AT&T retail store I ask for the $25 pay as you go plan & ask for serrated data as well? Of so how much is the data and would they add or to my refill or does it come separately? Step by step please and thank u!