It's the successor of the Windows 8 and Windows Phone generators.
Windows Universal Apps run across multiple Microsoft product families with nearly the same code—including PCs, tablets and smartphones.
In fact, Windows 10 represents the culmination of the platform convergence journey with Windows now running on a single, unified Windows core.
This generator has been included in early beta versions of GeneXus 15.
Due to lack of announcements related to specific plans for mobile phones from Microsoft, at least during 2016, market trends, among other reasons, GeneXus has stopped the development work for this generator.
Nevertheless, the bits of the generator are still included in GeneXus 15 and code generation for this platform keeps "as is".
This convergence enables one app to run on every Windows device – on a phone, tablet or laptop, or the PC, just by generating one code for all.
From the user's perspective, he will develop a Smart Devices application. The generated apps run on the desktop, and mobile devices (only varying their layout).