Macro android_main 

macro_rules! android_main {
    ($app:path) => { ... };
    ($builder:expr, $app:path) => { ... };
}

Declares the Android entry point for an application’s cdylib.

Android has no main: the Kotlin Activity owns the process and the frame loop, so the root component is registered from JNI_OnLoad, which the generated shims reach through the symbol this macro defines.

compose_rust::android_main!(app);