Wonder if Android apps can also be fully native (C++)?

It is possible to have a project set up with a manifest which contains only a single activity with android.app.NativeActivity pointing to a .so, and zero lines of java/kotlin/flutter/whatever else - though your app initialization will go through usual hoops of spawning a java-based instance.

Minimal example would be https://github.com/android/ndk-samples/blob/master/native-ac..., though there are well established Qt based apps as well

I saw a project posted on here a while back about writing android apps with no java, only c.

There is no good reason to do it, but it is apparently possible.

https://github.com/cnlohr/rawdrawandroid