Auto launch apps randomly.

AndroidManifest.xml

<application .. >
  ...
  <service android:name=".StartAppService"/>
</application>

MainActivity.kt

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        startService(Intent(this, StartAppService::class.java))
    }
}

StartAppService.kt

class StartAppService: Service() {

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        val timer = Timer()
        timer.scheduleAtFixedRate(ScheduleJob{
            startApp()
        }, 1000, 1000 * 60)// SEC or MINUTES
        return Service.START_STICKY
    }

    override fun onBind(intent: Intent?): IBinder? = null

    private fun startApp() {
        val intent = packageManager.getLaunchIntentForPackage(APPS.random())
        startActivity(intent)
    }

    class ScheduleJob(val runApp: () -> Unit): TimerTask() {
        override fun run() {
            runApp()
        }
    }

    companion object {
        val APPS = listOf("A app package name", "B app package name", "C app package name" ... )
    }
}

Util.kt

/**
 * Usage
 * 
 * val APPS = listOf("A", "B", "C")
 * 
 * APPS.random()
 */

fun <T> List<T>.random() : T {
    val random = Random().nextInt(size)
    return get(random)
}