Microsoft has released the new version of Windows Phone (codenamed "Mango") to device manufacturers, and it seems Japanese consumers will get to try it first -- as early as September.

The Microsoft blog said the release to manufacturing (RTM) build of Mango 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 update for current Windows Phone handsets will be ready this fall, and of course will come pre-installed on new Windows Phones," the blog read.

According to The Register, KDDI said it would be launching the first Mango handset by September and the device will reportedly be made by Fujitsu Toshiba Mobile Communications. The device, apparently waterproof, is expected to come with 3.7-inch display and 32GB memory and packs a whopping 13.2-megapixel camera. It will include Bluetooth, Wi-Fi, a powerful battery and will run on CDMA network.

The rest of the world will probably have to wait a bit longer.

Mango has been making a buzz since May when Microsoft gave a sneak peek of its newest mobile OS. It has hundreds of new features, including:

> New e-mail Conversation View: Allows the user to efficiently participate in long e-mail discussions with friends and co-workers.

> Threads: Combines the user's text, IM, and Facebook chat all into one conversation.

> True Multitasking: Mango is the first mobile OS from Microsoft to offer true application multitasking.

> Powerful Search Function: Mango connects apps to search results and deepens integration within the Hubs like Music and Video and Pictures.

> Internet Explorer 9: Mango includes IE9 for faster Web browsing and support for new HTML 5 Web sites.

Besides Fujitsu, other companies that are expected to release Mango-powered smartphones in the near future are Samsung, Nokia, Acer and ZTE.

Mango (or Windows Phone 7.5) is expected to give the much-needed boost to Microsoft, whose performance has "gone from very small to ... very small," according to CEO Steve Ballmer.

According to IDC, in the first quarter of 2010, Microsoft's market share of smartphones was 7.1 percent and in the same period of 2011 it slipped to 2.7 percent.

In terms of handsets shipped in the two periods, Microsoft saw a decline of 1.1 million, falling from 3.9 million to 2.8 million.

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