Currently, I am on a Family Plan with my aunt and her family on ATT. The bill is so low for my portion that she pays for it herself. Like $6, but I don't know for sure. I have unlimited texting and share minutes with 3 other people that roll over each month. I don't have internet access or multimedia messaging either. Pretty basic. But my sis is thinking of selling her iphone to me and I was wondering if I could switch my SIM card with hers and how much I would have to pay for the Data Plan and any other features needed....
Help, please.

Help, please.