Microsoft will now have unified branding for apps in the Windows 10 generation. During WinHEC, engineer Don Box mentioned that the company would be calling the universal apps “Windows apps.” Since the universal apps work across the PC, mobile, and Xbox One platforms seamlessly it makes sense to run with one name for them all.
The naming of Windows apps hasn’t caused confusion off the bat so much that it has caused “incorrect” naming. Instead simply calling Windows 8 apps “apps” or “Windows apps” some called them “Metro apps” with Metro being the design used for Windows 8.
With the term “Windows apps,” Microsoft isn’t so much branding the family of apps, but tossing it up and letting it be know that these apps are associated with the OS and not an element of the OS. It also helps in preventing any reason to call this generation of apps “Windows 10 apps” or something along those lines.