title: iOS Push Notifications with empty aps dictionary
body: <p>Doing research to try and pick a direction for notification types.  I'd like to be able to notify my app that there's new data to be refreshed but not bother the user with the popup/notification message.  The idea is that the same notifications go out if the app is open or closed and when this "special" message arrives and the app is open it knows to fetch data.</p>
  
  <p>My idea was to send an empty aps dictionary like example 5 at the bottom of this <a href="http://developer.apple.com/library/mac/#documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/ApplePushService/ApplePushService.html#//apple_ref/doc/uid/TP40008194-CH100-SW9" rel="noreferrer">apple document</a>.</p>
  
  <p>My question is what will happen when this type of message is received?  It says it'll clear the badge but will some sort of default message appear to the user? Or will this be completely silent?</p>
  
  <p>Follow up question, is there some better way to do this other than checking if the app is running and telling my server to start sending "special" payloads (I'd like to handle everything through push)?</p>