title: Replacement for old GetAppUsers call to see a user's friends who use my application?
body: <p>One immensely useful call in the old REST API is <code>Friends.getAppUsers</code>. This call returns all your friends that are using an application. Sadly, this is not in the <a href="http://en.wikipedia.org/wiki/Facebook_Platform#Open_Graph_protocol" rel="nofollow noreferrer">Open Graph</a> API. There is a good Stack Overflow post about it, <em><a href="https://stackoverflow.com/questions/2785093/facebook-friends-getappusers-using-graph-api">Facebook 'Friends.getAppUsers' using Graph API</a></em>.</p>
  
  <p>However, it is possible to use the Graph API to make <a href="http://en.wikipedia.org/wiki/Facebook_Query_Language" rel="nofollow noreferrer">FQL</a> calls as can be seen here in the <a href="https://developers.facebook.com/tools/explorer?method=GET&amp;path=fql/%3Fq%3DSELECT%20uid,username,%20is_app_user%20FROM%20user%20WHERE%20uid%20IN(SELECT%20uid2%20FROM%20friend%20WHERE%20uid1%20%3D%20me())%20AND%20is_app_user%3D1" rel="nofollow noreferrer">Graph API explorer</a>.</p>
  
  <p>I thought that maybe I could make the following call using the C# SDK:</p>
  
  <pre><code>fb.GetAsync("fql/?q=SELECT uid,username, is_app_user FROM user WHERE uid IN(SELECT uid2 FROM friend WHERE uid1 = me()) AND is_app_user=1");
  </code></pre>
  
  <p>However, this returned an error. Is there a way to work around the lack of the <code>GetAppUsers</code> call using the existing C# SDK?</p>