T-Mobile, despite Q3 growth, continues to be hurt by its lack of iPhone

Once again, so much depends on the iPhone.

T-Mobile announced today that it added 126,000 subscribers during its third quarter, bringing its total to 33.7 million, up from 33.6 million a quarter earlier. It was its first customer growth in a year, helped by its unlimited Value plans and a growing portfolio of 4G Android smartphones.

Even stuck in the awkward middle ground of waiting to hear whether AT&T will become its parent company, it managed to post revenue that exceeded analyst estimates. But as the only top-four carrier without an Apple handset, churn continues to be an issue.

"Attractive prepaid offerings helped us add customers in the third quarter of 2011 and data ARPU grew as smartphone adoption continued to increase," T-Mobile CEO Philipp Humm said in a statement. "Discipline on the cost side contributed to year-on-year margin improvement, while postpay churn, in particular related to the iPhone 4S launches by competitors, will continue to be an area of concern.”

The iPhone brings with it certain challenges, but the one problem it undoubtedly helps is churn.

"That is the number-one reason customers churn — lack of iPhone," Sprint CEO Dan Hesse told attendees at an industry event early this fall (CP: Sprint CEO Hesse chats 'fireside' about what Sprint does and doesn't have), before Sprint finally announced it had struck a deal with Apple. Even C Spire, formerly Cellular South, now offers an iPhone.

Andrew Sharrad, T-Mobile's senior vice president of marketing, has shared the reason it doesn't have an iPhone isn't for lack of want, but that Apple "has not developed a version of the iPhone with technology that works on our fast 3G and 4G networks." Were Apple to offer one, he added, it would certainly be a "compelling option" for subscribers.

However, that doesn't seem likely anytime soon.

“We’ve gotten better at winning new customers, but the rate at which subscribers are leaving still isn’t satisfactory,” Rene Obermann, CEO of T-Mobile parent company Deutsche Telekom, said during the earnings call. “It looks as though that’s still going to be the case in the fourth quarter.”