So I am looking to buy a iphone from someone and I am wondering if I can take my sim card from my old razor and put it in a iphone 3g and call att to add the 20/30$ data plan. I don’t know if this matters but the sim card is from the old Cingular and it says 64k smart chip. Also would it just be the 30$ data plan or in there a “iphone plan” that you have to have besides the data.

 

 

Thanks,

Connor