If I am correct in my understanding of how it works, Linux versions should work on Android as well.

Android is kind of a special child, it uses custom kernel modules like Binder (IPC framework) and Ashmem (Android's garbage collector/memory manager).

The Linux system calls used by cosmopolitan work fine on Android provided they aren't blocked by seccomp policy. Some of those blocks make sense, others not so much. Yesterday I discovered I could use all the stat variants but not statx.

I believe the features provided by standard C libraries are well covered by the set of allowed system calls.

Funny you mention that. A few weeks I tried building cosmopolitan inside a Termux environment but the makefile didn't like it. At the time I gave up and used my laptop because I was focused on developing a feature. I wonder if I could get it to work now.