title: adMob contentURL parameter purpose
body: <p>Reading the <a href="https://developers.google.com/admob/ios/targeting" rel="nofollow">official documentation</a> regarding the adMob contentURL parameter it is not clear what is the purpose of passing a URL.</p>
  
  <p>The doc says:</p>
  
  <blockquote>
    <p>Content URL</p>
    
    <p>Applications that monetize content matching a webpage's content may pass a content URL for keyword targeting.</p>
    
    <p>For example, if your app serves blog articles and is requesting an ad while showing content from the article <a href="http://googleadsdeveloper.blogspot.com/2013/10/upgrade-to-new-google-admob.html" rel="nofollow">http://googleadsdeveloper.blogspot.com/2013/10/upgrade-to-new-google-admob.html</a>, then you can pass this URL to target relevant keywords.</p>
  </blockquote>
  
  <p>Will they fetch the page in realtime or use historical data to look for keywords to use?</p>