... but he can't afford the data plan. I've been looking around for info for a few days but I'm confused. If you can help guide me, I'd really appreciate it and I'm sorry if this question has been asked before. I got the new 3GS and I'm using it with my original SIM card, taken out of my 1G. Can my brother put his AT&T SIM card in my old 1G and use it as a phone & iPod without buying AT&Ts data plan? In other words, keep his existing AT&T phone service but use my 1G? Thanks in advance.