Currently on AT&T grandfathered unlimited data. Current contract began 11/05/2012 and I purchased a Galaxy Note 2 with my upgrade at the time. Screen broke and is usable but I am looking to purchase new phone and get back to an iPhone, preferably 5S. From my reading, is it my understanding that my best bet is to add a line to my current plan, thus making it a family plan and using the new line to purchase a subsidized iPhone and then transferring my current number to the new phone? Everything I am reading indicates you can do this without losing unlimited data and it will only cost you $10+ tax for 24 months. I obviously will not have a data plan on the second line and will probably purchase a go phone to have a serial number/sim attached to the dummy line. Is that really my only option other than buying the phone at retail price?