Microsoft released Windows RT Update 3
Update 3 (KB3033055) for Windows RT 8.1 is available in Windows update for users of this version of the operating system, as Microsoft promised a few months ago.
The company has not yet announced the release this update officially, but it is reported that the update is propagated waves. So if your device it not all available, just be patient and wait your turn.
Unfortunately and to the disappointment of users of Update 3 contains just one feature of Windows 10, namely, the new start menu with tiles. What’s worse, it is not the same menu that is available in Windows 10 (based on XAML), and a version based on the code for Windows 8.1. Fortunately, if the «start menu» don’t like it, still have the option to use the old start screen in full screen mode.
And if someone has doubts, no, this update adds support for universal apps.
In General, this is a pretty strange decision to release an update of this type (which can be equated to Windows Phone 7.8), which does not add any support for ecosystem store apps in Windows RT or tablet mode, nor anything else except a few people need to «start menu».