title: Sending push notifications with Passbook API
body: <p>I'm trying to send some push notifications with the Passbook API. I've created the following JSON object that I send to the APNS server:</p>
  
  <pre><code>$payload = json_encode(array('aps' =&gt; array('alert' =&gt; 'Hello World!')));
  </code></pre>
  
  <p>However, this message does not arrive. I've been searching on internet on how to do this when using Passbook, but I can't find it. When I send an empty payload like this:</p>
  
  <pre><code>$payload = json_encode(new ArrayObject());
  </code></pre>
  
  <p>the (update) notification arrives and the pass gets updated.</p>
  
  <p>So, does anyone know how I should send a custom message to the APNS server?</p>
  
  <p>Thanks in advance!</p>