Yes, you should be able to use a T Mobile SIM card on any T Mobile phone.
No. The networks used by T-Mobile and US Cellular are incompatible with each other.
Yes, all major US telephone companies are use in Puerto Rico.
no
Yes. You just need to put a t-mobile SIM card in it.
T-Mobile and AT&T are both cell phone providers in the US. Soon, they will be one company if the sale is approved by the government.
T mobile.
T-Mobile phones do not work with Verizon's Service. T-Mobile phones use Sim Cards and Verizon does not, so they are not compatible.
T-Mobile Headquarters 800-318-9270
You can't get a T Mobile service on a phone that's not T Mobile unless you get it unlocked. Once the phone is unlocked, you can use your T Mobile SIM card on it or any other GSM SIM cards worldwide.
You can still use it
Not yet in the US (nobody really knows when), but outside the US, some T-Mobile subsidiaries do, from what I've read. If you use your iPhone in the US, you can unlock your iPhone using one of several hacking tools, and then T-Mobile will be happy to sign you up, either for phone-only service, or phone and data. It's a little cheaper than ATT, and depending on where you use the iPhone, you might get better (or worse) reception than with ATT.