title: Firebase silent notification does not start up a closed iOS app
body: <p>Can FCM silent notification start up a closed iOS app?</p>
  
  <pre><code>Request Type: POST
  
  Request URL: https://fcm.googleapis.com/fcm/send
  
  Request Headers:
  
  Authorization -&gt; key=MY_KEY
  
  Content-Type -&gt; application/json
  
  Request Body:
  
  {
    "to": "/topics/my_topic",
    "content_available": true,
    "data": {
      "contentAvailable": 1
    },
    "priority": 10
  }
  </code></pre>
  
  <p>However, this payload does not start up my iOS app if the user closes it.</p>
  
  <p>How to make the iOS to start my app whenever a silent notification is received?</p>