title: Google Cloud Messaging , how to control the message queue?
body: <p>I have implemented Google Cloud Messaging on Android. When the device is no internet connection and receives messages accumulate in queue and when he returns to have internet connection receives all. This is a problem for me. I want that when the device has more than one message queue receives only one. This is possible? </p>
  
  <p>Is there any way to see the queue on the server? </p>
  
  <p>Thank you</p>
  
  <p><strong>Update...</strong></p>
  
  <p>Work fine...</p>
  
  <pre><code>$fields = array(
              'registration_ids' =&gt; $registrationIDs,
              'data' =&gt; array("message" =&gt; $message),
              'collapse_key' =&gt; $collapse_key,
          );
  </code></pre>