The Windows Phone 7.5 update, also known as Mango, will reach all Windows phones in the autumn, but the IS12T is the first device we've seen with Mango built in from the kick-off.
The IS12T includes Mango features such as enhanced live tiles, multitasking support, Internet Explorer 9 and a people hub that pulls together messages and social-network updates from friends. Mango also adds dancing Xbox Live avatars and improved integration with Twitter and LinkedIn.
Tokyo-based site DigInfo TV took the IS12T and Mango for a spin at the phone's launch. Click play on the video below to see the new phone in action.
It's unlikely we'll see the IS12T in Blighty, but it's certainly a tasty little number. The phone packs a 1GHz Qualcomm processor, a 13.2-megapixel camera that shoots 720p video, and 32GB of memory. It comes in citrus yellow, hot pink or black, and the distinctive coloured tiles in Windows Phone can be changed to match the colour of the handset. Announced this week by Japanese phone network KDDI, it's the first Windows Phone in the land of the rising sun.
And because the Japanese are never happy with one major selling point when they can have 15, the IS12T is waterproof.
We're holding out for Nokia's Windows phones before we get too excited about Mango. The Sea Ray prototype has been glimpsed in the wild, and Nokia's first Windows phones are expected before the end of the year.
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