A silent remote notification, introduced after iOS 7, lets apps run code in the background to update content from the server without alerting the user.
Use cases
It’s ideal for enhancing user experience in multimedia chat, email updates, and subscription-based content sync via notifications.
Background code execution
When the app receives the notification, it runs this code in the background:
-- (void)application:(UIApplication didReceiveRemoteNotification:(NSDictionary fetchCompletionHandler:(void result))handler *)application *)userInfo (^)(UIBackgroundFetchResult
By now, only messages sent through the Server API support silent push notifications.