Originally Posted by sarstube
it's bs. you can switch back and forth provided you have an adapter for the iphone4's micro sim card. on an iphone 1g, 3g, 3gs you can switch it no problem.
i did it with my captivate and even now my inspire that i purchased off contract (had an upgrade but didn't want to burn considering how cheap the phone is)
It was a 3G and they just swapped them out. Now my iPhone just says No SIM. all the time. Kind of want an extra SIM just to get rid of the message. Guess I'm just to lazy to pull it out and switch. Does the battery need to be pulled on the Captivate before pulling the SIM? Wonder if I can just get a cheap AT&T SIM off Ebay and pop it in the old iPhone to get rid of the message without buying a phone plan of anything. Its mainly just used for Skype wifi calls right now. My other VOIP apps wouldn't work without a SIM for some reason.