Microsoft’s smartphone plans are starting to take shape.

The Wall Street Journal reports that the company has already begun testing its own smartphone design with Asian suppliers. Sources say the device’s screen will measure between four and five inches, making it pretty standard as far as smartphones go.

But while Microsoft is already testing its phone, the company isn’t sure it will actually end up mass producing such a device. As we’ve noted before, the creation of the phone will depend largely on the success of Windows Phone 8: Microsoft will probably be in less of a rush if existing Windows Phone 8 devices are selling well.

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Still, it’s telling that Microsoft’s smartphone development has already progressed as far as it has. While a Microsoft smartphone could spur further interest in the Windows Phone platform as a whole, the device will also show that Microsoft isn’t confident leaving Windows Phone solely in the hands of its hardware partners.

The most key of these partners is, of course, Nokia, which is betting what feels like its entire future onWindows Phone with its Lumia 920 and Lumia 820, which launch this month.

In terms of timing, previous reports speculated that a Microsoft smartphone wouldn’t see a release until mid-2013, likely long after Nokia had its chance to try its own hand at success.

Photo: Devindra Hardawar/VentureBeat

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