Yes
Apertus.io is written in C#. Have you tried to run it with Mono for Linux, Mac and Android?
https://www.mono-project.com/
We have not.
But I love the idea!
I compiled mono (configure, make, make install etc) and it installed correctly under Lubuntu 17.10. I did "mcs hello.cs" and got hello.exe. Then "mono hello.exe" gave "Hello Mono World".
Now I need to start Apertus. I see a ADD.csproj, ADD.sln, Main.cs etc. "xbuild" seems to run.