> GNOME supports

I've heard that there's *support* -but is the experience of having a touchscreen on an ubuntu device actually usable and good?

For example some random GUI app you're likely to use on ubuntu is the experience not broken?

I guess Chrome is the first thing that comes to mind.

My only issue with Chrome on touchscreen was the lack of 1:1 scroll/zoom gestures. As a Firefox user it was something that I got used to, but I just updated Chromium and apparently that's been fixed now too.

Besides that, it all works about as well as you'd expect it to. You can drag the window around by the tab bar and tap-and-hold to pull up a context menu.