public void servicioOnline(){


    final ActivityManager activityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);

    final List<ActivityManager.RunningServiceInfo> services = activityManager.getRunningServices(Integer.MAX_VALUE);
    for (int i = 0; i < services.size(); i++) {
        String packageClassName = services.get(i).service.getClassName();
        if (packageClassName.equals("nombre_paquete_de_la_otra_apk")) {

            System.out.println("Service Nr. " + i + " :" + services.get(i).service);
            System.out.println("Service Nr. " + i + " package name : " + services.get(i).service.getPackageName());
            System.out.println("Service Nr. " + i + " class name : " + packageClassName);

            //return true;
        }else{
            System.out.println("hay problemas...");
        }

    }
    //return false;
}

public static boolean verAppEjecutada(final Context context, final String packageName) {
        final ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        final List<ActivityManager.RunningAppProcessInfo> procInfos = activityManager.getRunningAppProcesses();
        if (procInfos != null)
        {
            for (final ActivityManager.RunningAppProcessInfo processInfo : procInfos) {
                if (processInfo.processName.equals(packageName)) {
                    return true;
                }
            }
        }
        return false;
    }