As Microsoft prepares to combine its Windows RT tablet operating system with Windows Phone, Microsoft executives are stuck with a tricky decision on branding for an upcoming OS that runs across both tablets and phones. Microsoft has Windows RT which runs on tablets, Windows Phone for phones, and Windows 8.1 for tablets and PCs. It’s a bit of a confusing mix for consumers to understand, but there are signs Microsoft might be moving away from using lots of different Windows names. Microsoft’s latest commercials for the Lumia 930 don’t even mention Windows Phone at all.