We're still a little ways away from Mango's official release, and already it's successor, Tango, may be skulking around in the shadows. Using an app called Dude, Where's My Update?, which tracks what versions of WP7 people are running on what devices, Japanese site Nanapho, spotted a previously unknown version 7.10.8200. As it turns out, this might be Tango, the expected interim release between "Mango" and "Apollo" aka Windows Phone 8.

Though Tango has not been formally detailed by Microsoft, Nanapho says that it will include better Bing, improved Bluetooth, Internet Explorer 10 and Skype integration. Most interestingly, there also seems to be some Nokia-specific programming. We know that the next major version of Windows Phone will be called "Apollo," and that news about Tango came from Compal, an ODM who will be manufacturing handsets for Nokia.

Source: Nanapho