AT&T will be the first US carrier to offer the much-talked about Mango, updating its new Windows Phone 7.5 phones lineup, according to media reports.

“AT&T also said all Windows phones handled by the company would be updated to the Mango version of the Windows Phone operating system this fall. Two of the new 4G devices are from Samsung, and one is from HTC,” NewsFactor Network reported.

AT&T has sold more Windows Phone devices than any other carrier a tradition it clearly intends to continue, announcing that it will launch three new 4G Windows Phones during the fourth quarter.

According to news reports, the Samsung Focus S, HTC Titan and Samsung Focus Flash, will all run the Mango update which this fall will also be pushed to all the Windows Phones that AT&T has already sold.

The Mango update to Windows Phone 7 offers a several improvements that Microsoft (News - Alert) hopes will help push its way up into the current mobile market, which is currently dominated by Apple and Android phones. The new HTC and Samsung Windows Phone devices will likely have a Sprint iPhone (News - Alert) 5 to compete against not to mention the same phone from Verizon and AT&T as well as Nokia handsets running Mango, AT&T officials said.

“The Samsung-made Focus S offers a 4.3-inch Super-AMOLED-Plus display, a 1.4-GHz processor, 4G-capable speeds, a front-facing 1.3-megapixel camera and a rear-facing 8-megapixel, and a width of only 8.55 millimeters,” according to NewsFactor.

The Samsung Focus Flash has a 3.7-inch Super0-AMOLED screen, a 1.4-GHz processor and a 5-megapixel camera. The HTC Titan has the largest screen of any AT&T phone, 4.7 inches and features a 1.5-GHz processor and an 8-megapixel camera with dual LED flash.

According to comScore (News - Alert), Microsoft had only 5.7 percent of the U.S. smartphone market as of July, compared with 41.8 percent for Android, 27 percent for Apple and 21.7 percent for Research In Motion, NewsFactor reported.

AT&T also said Monday other Windows phones that would be updated to Mango included the HTC HD7S, the HTC Surround, the LG Quantum (News - Alert) and the Focus. In its statement, AT&T officials described its decision to push the Mango update to all its Windows Phone customers as taking its Windows Phone “leadership to a whole new level.”

Pricing and ship dates for the Mango devices have not yet been announced.

Last month, TMCnet reported AT&T’s third and fourth-quarter release schedule shows several new devices being released on the network, including six Android (News - Alert) phones. According to information obtained by PocketNow, in addition to the Android phones running Android 2.3.3 or 2.3.4 Gingerbread, the list included two BlackBerry 7 devices and two Windows Phone 7.5 Mango devices. 

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