Our startup develops a HTML5 game editor called Construct 2, which is a Windows desktop app (Win32). We've been running about five years successfully with that.

Our startup develops a HTML5 game editor called Construct 2, which is a Windows desktop app (Win32). We've been running about five years successfully with that. I'd say depending on the market it can still be relevant, but I don't know for how much longer - Windows in particular seems to be trying to drag developers away from Win32 and the new Windows Store UWP apps. Note that Windows Phone and "Windows RT" can only run Windows Store UWP apps, with poor support for Win32. MS continue to push UWP hard and I'd expect to see more MS hardware in future with no Win32 support, which is a little worrying, but doesn't seem to be happening fast enough to cause any kind of panic. I'd add while mobile seems to be the trendy place to start a startup, most productivity apps are still easier and faster to use with a keyboard and mouse. So desktop-first can make sense sometimes.