Ok so i have Tmobile Samsung Galaxy S2 and i basically want the iphone 4s. Now how do i so that? Can i just sell my S2 and just buy an att one and will it work? Or will my sim card be like to big or something? Do i need to buy an unlocked iphone 4s? Will the phone work like shit if i am able to switch it up? How does this all work lol? Thx guys