Over 13 carriers to choose from
phone carriers use 2 types of wireless technologies these are gsm &cdma
It is best to think of it in terms of radio. fm radio stations can be recieved on any fm radio but not on a am radio. am radios can pick up any am station but not fm stations.
At&t t-mobile use gsm radios
sprint & verizon use cdma
Any phone once unlocked or flashed will work with its coriponding radio style.