title: Xamarin.Forms iOS shows "Master" and "Detail" instead of just back icon or menu icon
body: <p>on Android, my app shows a little arrow in the navigation bar up top that, once clicked on, brings you back one screen. But iOS, ofc is special, shows the word "DETAL" and "MASTER". </p>
  
  <p>The do the same (open the menu, go back) but its wierd.</p>
  
  <p>THis is how I open the page:</p>
  
  <pre><code>    button_test.Clicked += delegate
      {
  
  
          Application.Current.MainPage = new Screen_MainMenu();
      };
  </code></pre>
  
  <p>Can someone tell me, what is going on and how to just make it show the arrow and not the words? </p>