As it settles into its post-merger life with MetroPCS, T-Mobile is rolling out the top-of-the line Nokia handset powered by Microsoft's Windows 8, the Lumia 925.

T-Mobile has an exlusive deal on the 925 in the U.S., although Vodafone, the British telecommunications giant that is a partner in Verizon Wireless, is distributing the device in the United Kingdom.

"T-Mobile is excited to continue building on our partnership with Nokia and Microsoft by bringing customers another exclusive device," the company said in a statement today.

First Windows LTE Device

The Lumia 925 will be the first Windows Phone 8 device to access the company's growing 4G, long-term evolution high-speed data Relevant Products/Services network Relevant Products/Services. A previous Lumia device, the 810, which was also a T-mobile exclusive back in November, will not be updated for LTE, the company said last month, although it has the hardware capability to do so.

The price and release date of the 925 have yet to be announced, but interested customers can register for updates. The 810 is currently available with no money down at the carrier, which now offers contract-free plans, but with $15 monthly payments required for two years.

The 925 features a thin, lightweight metal design and 4.5-inch PureMotion HD+ display, up from the 810's 4.2-inches. Other featured specs include a 1.5 gigahertz dual-core Snapdragon processor Relevant Products/Services, an 8.7 megapixel camera with Optical Image Stabilization and dual-LED flash Relevant Products/Services, a gig of RAM, 16 gigs of memory Relevant Products/Services and 7 gigs of free storage Relevant Products/Services on Microsoft's SkyDrive cloud Relevant Products/Services.

"Getting a high profile exclusive and differentiated flagship device in a portfolio is always a win for any carrier," Strategy Analytics mobile analyst Neil Shah told us. "It improves the portfolio mix and thus the subscriber stickiness. T-Mobile with Lumia 925 won't have to worry now about losing hundreds of thousands of current or prospective subscribers [who are] aspiring flagship Windows Phone devices to AT&T or Verizon."

He added that the carrier, owned by Germany's Deutsche Telekom, has a brighter future now than it did after federal regulators killed its proposed merger with AT&T.

"The overall prospects are improving with getting hold of not only MetroPCS subscribers but valuable spectrum assets and some markets and segments (such as Latino) where they had lesser share," said Shah.

Not Gangbusters

But another analyst, Ken Dulaney of Gartner Relevant Products/Services Research, said exclusive devices on a platform that is struggling to gain market share isn't much of a coup.

"If it was going gangbusters, all would have it," Dulaney said of the Lumias. "Windows Phone 8 still has to prove itself in much higher volume for any carrier to claim they have scored a huge win for a particular device. Also, it's not clear whether others will have it as well but just under a different model number. Nokia is not going to lock themselves out of other carriers. They need lots and lots of business Relevant Products/Services."