iPhone & GSM service

[light3944]

I have a pretty basic question... If I were to buy a GSM iPhone could I just take my SIM Card from my Treo and just start using it without changing my current AT&T plan? I know on the website they are showing special plans for the iPhone but I am currently on a $20 a month Unlimited Data Plan that is no longer avalible. I bought my Treo 680 from Palm because I knew that if I bought it from AT&T they would switch me to the $45 a month plan so it was cheaper to pay $200 more for the phone then $25 more a month on my plan.

 

[jay_man2]

No, you couldn't. You have to activate the iPhone with the SIM card that coms with it, then your old SIM card s no longer valid. But the unlimited data plan with 200 SMS messages is only $20 for the iPhone, not $45 like the Treo, added to the cost of whatever minute plan you have.