title: How to update the view of an app on ios device b from device a
body: <p>I have built a webservice that handles all data inputted and outputted for two seperate apps yet closely related: 'Sales' app, and an 'Admin' app for a particular company.</p>
  
  <p>Every time a sales assistant takes an order over the phone and inputs it into the sales app closing the deal the admin app should be notified that a sale has been made. (sales are not made frequently since they are bulk sales). The first thing that popped up in my head was to use Apple's push notification service since this would alert the admin app if the admin was closed.
  Im sure that is correct.</p>
  
  <p>Here is where I start to feel uncertain.
  What happens in the situation where the admin app is already open, how can the admin app be updated as soon as a sale is made? I understand that push notifications can still be received when the admin app is open and therefor be notified right away when a sale is made on the 'sales' app. </p>
  
  <p>Talking only in terms of <strong>when the application is open, is there a way for when the admin application to be notified straight away as soon as a sale has been made; without using apple's push notification service; and without regularly refreshing the admin's app page where a webservice function would be called at regular intervals to see if any recent sales have been made, which i feel is not a good way forward?</strong></p>
  
  <p>Or is the correct and appropriate way to use only the push notification service?</p>