<p>According to my son, it’s T-mobile. We’ve been using it for about 2 years now, so we did not have to switch. And by the way, if your cell phone is broken, T-mobile has a nice plan whereby you can get a new one - and of course sign up for a year - for free.</p>
<p>ps. - If the phone is a bit expensive, then you pay for the new one but not as much as you would have if you had to just buy a new cell-phone.</p>