The content of my publication needs to be updated throughout the day. Can I initiate a Newsstand background download more than once in a 24-hour period?
Allowing multiple background downloads for multiple apps would drain system resources, so Newsstand apps are limited to one background download initiated by push notification each day. If you send additional notifications to a device that attempt to initiate a background download, those notifications will be delivered to the device but ignored by Newsstand Kit.
If you want your Newsstand app to deliver breaking news, consider sending an issue via background download and downloading a small amount of additional, up-to-the-minute content when the user launches your app.
For test purposes on development devices only, you can override the built-in limit and initiate more than one background download in a 24-hour period by setting the user default @"NKDontThrottleNewsstandContentNotifications". See Listing 1.
Listing 1 Setting the user default NKDontThrottleNewsstandContentNotifications
[[NSUserDefaults standardUserDefaults]setBool: YES forKey:@"NKDontThrottleNewsstandContentNotifications"];