title: AdMob not showing ads in iOS simulator
body: <p>I am trying to use AdMob on an app (built for iOS 4.0)</p>
  
  <p>I've added the sample code available in the tutorial <a href="http://code.google.com/mobile/ads/docs/ios/fundamentals.html" rel="noreferrer">http://code.google.com/mobile/ads/docs/ios/fundamentals.html</a> which is the following (I've changed the adUnitID):</p>
  
  <pre><code>// Create a view of the standard size at the bottom of the screen.
  bannerView_ = [[GADBannerView alloc]
                 initWithFrame:CGRectMake(0.0,
                                          self.view.frame.size.height -
                                          GAD_SIZE_320x50.height,
                                          GAD_SIZE_320x50.width,
                                          GAD_SIZE_320x50.height)];
  
  // Specify the ad's "unit identifier." This is your AdMob Publisher ID.
  bannerView_.adUnitID = @"XYZ";
  
  // Let the runtime know which UIViewController to restore after taking
  // the user wherever the ad goes and add it to the view hierarchy.
  bannerView_.rootViewController = self;
  [self.view addSubview:bannerView_];
  [self.view bringSubviewToFront:bannerView_];
  
  GADRequest * request = [GADRequest request];
  
  // Initiate a generic request to load it with an ad.
  [bannerView_ loadRequest:request];
  </code></pre>
  
  <p>Doing this nothing happens, no ad is shown and the number of requests in my AdMob app page increase erratically (i.e.: I can't seem to notice a pattern), but the most important is no ad is shown.</p>
  
  <p>If I add the following code:</p>
  
  <pre><code>GADRequest * request = [GADRequest request];
  
  request.testDevices = [NSArray arrayWithObjects:
                         GAD_SIMULATOR_ID,                               // Simulator
                         nil];
  
  // Initiate a generic request to load it with an ad.
  [bannerView_ loadRequest:request];
  </code></pre>
  
  <p>I get the "Success! You are now ready to travel through the App Galaxy" default banner, but only this one.</p>
  
  <p>So my questions are:</p>
  
  <ul>
  <li>Aren't the sample code enough to show ads? Why I never see an ad with the sample code?</li>
  <li>As far as I understood, requests mean the number of times my app asked for an ad to be shown. I also understood that not every request is replied with an ad (otherwise the fill rate would be 100%), but still, I NEVER saw an ad, what am I doing wrong?</li>
  </ul>
  
  <p>Thanks in advance.</p>