With Apple's Oct. 4 launch event of the iPhone 5 a mere week away, there's a growing amount of chatter regarding the iPhone. The chatter isn't just about the device, but also about who will sell it. AT&T and Verizon Wireless, current Apple partners, are shoe-ins for the iPhone 5. Sprint is on deck for the iPhone 5, though it's not 100% confirmed yet.

T-Mobile, the fourth-largest carrier in the U.S., will not carry the iPhone 5. We learned as much last week through unofficial channels when an executive let the detail slip in an internal document. Now, it is official.

T-Mobile USA Chief Marketing Office Cole Brodman published an open letter to customers on Monday explaining why it will be the only major carrier not offering Apple's smartphone.

"We've heard from many customers who love their T-Mobile service, but are disappointed that we don't carry the iPhone," wrote Brodman. "To these customers, first, thank you for your business. Please know that we think the iPhone is a great device and Apple knows that we'd like to add it to our line-up."

Brodman is clearly blaming Apple here. The reason T-Mobile doesn't have the iPhone, according to Brodman, is because Apple won't allow T-Mobile to sell it. But wait, there's more.

"Today, there are over a million T-Mobile customers using unlocked iPhones on our network," Brodman continued. "We are interested in offering all of our customers a no-compromise iPhone experience on our network."

T-Mobile has shared this figure before, but it is still stunning to think about. More than one million T-Mobile customers--representing 3% of its subscriber base--have either paid full price for the iPhone, transferred it from AT&T to T-Mobile, or took some other measure to get the device they want on the network they want.

In order to do this, they had to unlock their iPhone, which is risky, and negates the warranty. Unlocked iPhones are often unable to update system software to get the newest features until the appropriate unlocking tools are made available. Worse, the iPhone only works on T-Mobile's 2.5G EDGE network, and has no access to 3G. In other words, using the iPhone on T-Mobile's network robs those customers of the full iPhone experience--and still more than a million have done this!

Brodman tries to steer customers back to T-Mobile's sanctioned handsets, despite his admission that they're happy to provide service to unlocked iPhones. "We continue to bring to market some of the most advanced, cutting-edge Android devices. We're very confident that these Android smartphones rival or beat any smartphone out there in terms of functionality, speed, overall experience, and features--including the iPhone," said Brodman.

Brodman freely admits that the company has made its bed with Android for now. A staggering 90% of T-Mobile's smartphone subscribers are using Android handsets instead of iPhones or even BlackBerrys.

"Android offers consumers the freedom of choice. You can choose from a variety of colors, screen sizes, slide-out keyboards, price points, and customization options, as well as enjoy the numerous benefits of open source innovation, cloud services, and amazing apps. This is why, for now, our focus continues to be giving customers the best that Android has to offer, coupled with 4G speeds that let you browse the Web faster than on average home internet."

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