Windows Phone 8 hasn't been officially announced yet by Microsoft, but it appears that at least someone at the company is currently testing an early build of the mobile OS. WPCentral.com reports that the Windows Phone 7 app I'm a WP7! has now registered someone using the software on a phone that has Windows Phone 8 "Apollo" build 8.0.9662.0 installed.

The site contacted the app's creator Scott Peterson who said, "It’s running from an Emulator, doesn’t appear to be spoofed, is using the default Emulator location, and the Time Zone Offset lines up with Pacific Coast…" All of that would seem to be consistent with someone at Microsoft testing the app on a build of Windows Phone 8 from their Redmond, Washington headquarters.

Furthermore, the same article claims that it has heard via unnamed sources that Microsoft has indeed begun internal testing of Windows Phone 8 on March 30th.

Microsoft has been silent about what new features will be introduced in "Apollo". However, it is known that the company was planning to add support for LTE networks in the next major update but later decided to fast track that addition for Windows Phone 7.5 so that Nokia's newly launched Lumia 900 could run on LTE networks. Windows Phone 8 is also expected to support smartphones with at least two processor cores along with other additions.

Microsoft should officially announce Windows Phone 8 later this summer, with an official launch expected in the fall of this year.

Image via WPCentral.com