A July 26 posting on the Windows Phone Blog by Terry Myerson, a Microsoft vice president of Windows Phone Engineering, said "the Windows Phone development team [has] officially signed off on the release to manufacturing (RTM) build of "Mango" -- the latest version of the Windows Phone operating system. This marks the point in the development process where we hand code to our handset and mobile operator partners to optimize Mango for their specific phone and network configurations." 

The "Mango" Windows Phone update, first promised in February by Microsoft CEO Steve Ballmer, enables application multitasking for background processing, audio and file transfer, and fast application switching. Holding a phone's back button down will provide a card-like view (pictured) of all running applications.

At a May 24 press conference, Microsoft outed the fall release of the Windows Phone 7 upgrade it's still -- as far as we know -- referring to only via its fruity code-name. (Various publications, ourselves included, have called it "Windows Phone 7.5," but this moniker remains unofficial.)

In May, Microsoft also released a Windows Phone Developer Tools Beta, with many new features but a modestly incremented 7.1 version number. For extensive details on the upgrades included in Mango and the revised developer tools, see our previous coverage.

Mango's conversation view (left) and Lync capabilities (right)
Source: Microsoft

Now that Mango has RTMed, its eventual release becomes a sure thing. As several commenters on the Myerson post have complained, however, carrier customization could delay the operating system upgrade's availability to end users until mid-September or later.

Responding to Myerson's "we can't wait to get Mango into your hands," commenter "slaythoven" complains, "Then stop going to carriers first and, after OEMs sign off, release it directly to us like Apple would."

Commenter "tsrbike" grumbles, "first the cell makers get to fiddle with it, then the providers get it. As we all know, AT&T loves to hold onto these things for a while (i.e. forever). So even if the cell makers only take six weeks to 'optimize,' AT&T and others will likely test for another six-plus weeks, putting us into October at the earliest."

On July 27, Cliff Simpkins, a Windows Phone 7 Product Manager at Microsoft, followed up the RTM announccement with word of a Windows Phone SDK 7.1 Beta 2 Refresh. He listed the following improvements on the Windows Phone Developer Blog:

• application platform APIs are now locked; you can feel confident to start getting ready for submitting your apps next month.
  
  
• the emulator now has a nifty screenshot capability built in,allowing you to quickly snap images of your app without the need forseparate tools or cropping time
  
  
• the profiler has been greatly improved and provides memory profiling
  
  
• you can install NuGet into the free version of the WPSDK tools
  
  
• the drop includes an initial peek at the Marketplace Test Kit;with the RC release, youll be able to use the included version of thistoolkit to test your XAP file against the same certification testingtools that we use when ingesting apps for the Marketplace

Simpkins added that developers can now download an updated Build 7712 of Mango. It is not identical to the RTM code being supplied to phone vendors and carriers, but may be considered a "genuine release candidate build," he wrote.

And the first Mango phone is?

In a morning press conference in Japan July 27, Toshiba and Fujitsu announced what was touted as the first phone that will come with Mango preinstalled. (We've heard the same claim made for Nokia's first Windows Phone, code-named Sea Ray, so it remains to be seen who will be first to cross the finish line.)

The Toshiba-Fujitsu IS12T
(Click to enlarge)

To be offered by Japanese carrier KDDI in September, the "IS12T" is described as being manufactured by Toshiba-Fujitsu, but only carries the Toshiba brand name as far as we can see. The device is "waterproof and dustproof," comes in yellow, pink, or black, and will sport an impressive 13.2 megapixel camera, according to the carrier.

The IS12T will feature a massive 32GB of memory, along with a 3.7-inch touchscreen that offers a resolution of 800 x 480 pixels. According to a machine translation of KDDI's announcement, the phone will weigh just four ounces, and measure approximately 4.6 x 2.3 x 0.5 inches.

The Toshiba-Fujitsu IS12T will pack 32GB and a 13.2 megapixel camera
(Click to enlarge)

KDDI didn't mention the phone's processor, but according to WPCentral, it will be a Qualcomm MSM8655.

The initial crop of Windows Phone 7 devices, whose hardware specifications were tightly controlled by Microsoft, all featured Qualcomm Snapdragon QSD8250 or 8650 processors. Both chipsets feature "Scorpion" application processors, but the QSD8250 supports only GSM, GPRS, EDGE and HSPA networks, whereas the QSD8650 supports both these and CDMA2000 1X, 1xEV-DO 0/A/B networks, according to the chipmaker.

A new Windows Phone 7 hardware specification unveiled at Microsoft's MIX11 conference in April added support for additional Snapdragon CPUs: the MSM7x30 and the MSM8x55. While still single-core devices, these processors allow OEMs to offer a wider range of clock speeds (from 800MHz on the MSM7x30 to 1.4GHz on the MSM8x55, according to Qualcomm), and they also provide Adreno 205 graphics -- said to offer over twice the performance of the Adreno 200 included with the earlier QSD8x50.

The Toshiba-Fujitsu IS12T
Source: KDDI
(click to play)

The IE9 browser in the Mango upgrade to Windows Phone 7 was shown beating the iPhone (left) and Android (far right) in this MIX11 demo
(click to play)

Jonathan Angel can be reached at jonathan.angel@ziffdavisenterprise.com and followed at www.twitter.com/gadgetsense.

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