After many, many days of trying to do business without an iPhone to sell, T-Mobile is pretty darn happy with its first day in the Apple business.

“Today has been gangbusters for T-Mobile,” Chief Marketing Officer Mike Sievert said in a statement toAllThingsD. “We experienced lines out the door this morning at nearly all of our almost 3,000 stores nationwide.”

Not all the lines persisted, though, with some critics of the company noting that later in the day stores were marked by a lot of no-longer-needed stanchions.

T-Mobile is making the iPhone a key part of its rebranding effort — a push that also includes ditching phone subsidies and long-term contracts and playing a serious game of catch-up when it comes to building its LTE network.

The company also launched an aggressive trade-in program, hoping to lure owners of iPhones on other networks to upgrade to a T-Mobile iPhone 5.

“Clearly they want the iPhone 5, and they are voting with their feet that they want it from T-Mobile,” Sievert said.

T-Mobile on Thursday launched a new national TV ad touting its iPhone 5. Print and digital ads will follow.

Via AllThingsD