public class Service extends android.app.Service {

    Handler h = new Handler();

    Runnable task = new Runnable() {
        @Override
        public void run() {
            ActivityManager activityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
            List<ActivityManager.RunningAppProcessInfo> procInfos = activityManager.getRunningAppProcesses();
            Log.d("tag", "chack!!!!!!!!!!!!!!!!");
            for (int i = 0; i < procInfos.size(); i++) {
                if (procInfos.get(i).processName.equals("com.mwdn.pricechecker")) {
                    h.postDelayed(task, 20_000);
                    return;
                }
            }

            Intent i = getPackageManager().getLaunchIntentForPackage("com.mwdn.pricechecker");
            startActivity(i);
            h.postDelayed(task, 20_000);
        }
    };

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        h.postDelayed(task, 10_000);
    }
}