This is a T-Mobile authorized dealer. I don't have T-Mobile, but my out-of-town guest does. As soon as she landed at Sky Harbor, she had absolutely no service on her phone. Calls to T-Mobile support weren't helpful, so the next day, we stopped here on our way up north. They, too, were unsuccessful getting her phone to catch a signal, and decided that it was just time to put the old phone to rest. She already knew what new phone to get next and we let them know we were kind of in a hurry. They were able to get us set up and out the door very quickly! The young lady helping us was friendly and really on top of things. Even though there were several other customers in the store, another employee was able to step aside and quicken up our process. It was the fastest new-phone transaction I've ever witnessed. Kudos to their super customer service!