Ref: Microsoft delivers promised Update 3 for Windows RT 8.1 | ZDNet Microsoft quietly made available a promised third update to Windows RT 8.1 tablets and PCs, which delivers a small subset of Windows 10 functionality, rather than the whole Windows 10 operating system. Microsoft has made available its third update for its Windows RT operating system for tablets and PCs running ARM.On September 15, Microsoft quietly rolled out Windows RT 8.1 Update 3, also known as KB3033055. That optional update, once applied, allows users to change some settings so that a new Start Menu -- one that looks something like the Windows 10 one but which isn't actually identical -- is displayed from the Start Button. Update 3 also now presents user account pictures in circular frames in some areas of the operating system, as well as an updated lock screen. I asked Microsoft officials late last night about Update 3, as I was looking to see if there were any other Windows 10 features included in yesterday's KB update. No word back so far. But I did download KB3033055 on my Surface RT device and did get the new Start Menu. Despite the fact that the unified Windows 10 Store includes apps built for ARM-based Windows Phones and as-yet-unannounced small ARM-based tablets running Windows 10 Mobile, Windows RT users cannot run new and updated Universal Windows apps -- even after applying Update 3. Universal Windows apps are meant to run on any Microsoft platform with a Windows 10 core, and so that leaves out Windows RT, Microsoft officials have said.