title: iOS: UITableViewController - when to refresh (design)?
body: <p>I have a UITableViewController that displays a list of messages. I use CoreData and NSFetchedResultsController to cash/store each object corresponding to a cell. I wonder when to refresh the table to be in sync with the server. On the one hand, I could go for manual refresh only, but I want the table view to be in sync automatically. On the other hand, I could refresh every time the table view appears, but that seems wasteful. 
  What is the normal approach in this case? Use Push Notifications and refresh every time a push is received? But what if the user disables push notifications?</p>