Drivers: Linux usually supports almost everything, there was even a build of Fedora for the Nexus 7.
UI: KDE especially has very good touch screen support, including a thing that automatically changes system UI when you connect a mouse, or keyboard, or so on, and switches between phone style, tablet style, desktop with touch, and desktop style on the fly. (Essentially Microsoft’s Continuum) Since 2012.
I used KDE Plasma Active on my Nexus 7 for some time, actually.
UI: KDE especially has very good touch screen support, including a thing that automatically changes system UI when you connect a mouse, or keyboard, or so on, and switches between phone style, tablet style, desktop with touch, and desktop style on the fly. (Essentially Microsoft’s Continuum) Since 2012.
I used KDE Plasma Active on my Nexus 7 for some time, actually.