I use it in a little WIP game engine. It's very pleasant, excellent little library. There's an online jsfiddle-esque demo here https://fiddle.skia.org/ if you want to try it out.
Mike’s AlphaMask (sold to OpenWave) didn’t share code with the original Skia but was kind of a Skia 2, with more flexible and clearer architecture than the original. This Skia—which, again, doesn’t share code with either of its predecessors—is a kind of version 3, with a tribute name back to that original Skia.
Skia would be more useful for graphical applications focused on vector graphics (diagrams, plots, layout editors, CAD...). And for general purpose 2D graphic platforms like browsers have.
For the UI I used imgui. Skia actually comes with an imgui backend (it's used for the Viewer tool) that is easy enough to hack into whatever you need.
Even I rather use SDL, written in C, than having to deal with getting to compile Skia across my platforms.
Then there is Cocos2d-x, SFML and OpenFrameworks as well.