I've used a 3gs from july 2010-august 2011 without any data plan on at&t. had just bought it from craigslist and was using it just fine. After that i upgraded to the Iphone 4S and gave my old iphone to my mom. She used it from oct-dec 2011 without data. However, last month at&t added data plan and its been a hassle for me to get it removed ever since. One rep said if the phone didn't use data the plan wouldn't be re-added and another rep said that if they system saw any smartphone it would automatically add. So I had to have them add another imei and remove the plan. Has anyone else successfully used an iphone without data plan? If so do you have any tips for me? I don't mind paying for data, but its just a waste bc my mom will never use it at all. She doesn't even use it on wifi.