title: Send and Receive remote events in iOS
body: <p>I am working on a iOS app for food delivery service. And I want to send events from shopkeeper end to customer end and vice-versa.</p>
  
  <p>My app is an iOS app. It is running on iPad 3 at shop end and a user can use iPhone for placing the order. So what is the appropriate method for communication and listening events? For example:</p>
  
  <p>Customer performs a food request. Shopkeeper should be notified immediately.
  When shopkeeper accepts it, an acknowledgment should be sent customer side.</p>
  
  <p>Thanks</p>