How Android Apps Work: Anatomy of a Modern Android App

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent { CounterScreen() }
    }
}

@Composable
fun CounterScreen() {
    var count by remember { mutableIntStateOf(0) }
    Column(
        horizontalAlignment = Alignment.CenterHorizontally,
        verticalArrangement = Arrangement.Center,
        modifier = Modifier.fillMaxSize(),
    ) {
        Text("Taps: $count", style = MaterialTheme.typography.headlineMedium)
        Button(onClick = { count++ }) { Text("Tap me") }
    }
}

android {
    namespace = "dev.example.counter"
    compileSdk = 36

    defaultConfig {
        applicationId = "dev.example.counter"
        minSdk = 26
        targetSdk = 36
    }
}