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

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-activity/app/src/main/AndroidManifest.xml https://github.com/android/ndk-samples/blob/master/native-ac..., though there are well established Qt based apps as well