During the Windows 8 lifecycle, the name for the store apps went from Metro to Modern but as we move forward with Windows 10, they will now simply be called Windows app



From Neowin:

The Modern app name has slowly transitioned to Universal apps as the company has championed the idea that you can write your code base once and run it on the various platforms that are now based on the Windows 10 core. But with all these names having come and now gone, Microsoft is looking to rename the apps yet again.

Microsoft is now referring to them as Windows apps; software that can only run on the desktop (Win32) will be known as Windows desktop applications. The slide below will help clarify this distinction, and it has become quite clear that this is how Microsoft intends to move forward with the app name slurry that it has created over the past three years.

  Goodbye, Metro, Modern and Universal; hello, Windows apps