Like the title says, when I build to Android using Unity buttons can be clicked and the UI blocks taps, but nothing is rendered. Unity 2019.1.5/Noesis 2.2.3.

What renderer are you using? For now, Vulkan is not supported.

That was the problem, thanks! No Unity project I've started ever had that as the default renderer, so I guess they recently changed that.

We are working on a Vulkan renderer.