The short answer is that Haxe isn't very good here yet. Many of the companies using Haxe are game studios, and so they just invent their own UI and it doesn't

The short answer is that Haxe isn't very good here yet. Many of the companies using Haxe are game studios, and so they just invent their own UI and it doesn't matter if it doesn't feel "native". In terms of the two approaches you mentioned: both can be used. There are various projects to "reinvent" a basic UI toolkit that works on NME, the cross platform graphics layer. These libraries would do what you mentioned first - have a consistent experience across platforms, but one that is foreign and probably not as polished. No libraries have really gained a huge amount of support for this yet, though it seems there are a few trying. The other approach - integrating with native UI - is also possible using Externs, which link in with an underlying system. I'm not sure how much use this has had. Some iOS features have externs, and on the desktop wxWidgets externs are around so this approach is possible. If you were to do this I guess you'd try to abstract away as many differences as you can, so that you need as little conditional compilation as possible. Not sure who is trying this at the moment. As I said though, UI toolkits is definitely not a strong point. My main development with Haxe is for JS / HTML, so I just use standard bootstrap / jQuery elements, which feel "web native" I suppose.