We use data-only push notifications to tell our app to check in with our servers for the latest information. These notifications happen when we know we have new information on the server.
This system generally works well for our large userbase. But for some users the notifications aren't received. We send a notification 10 times in 40 minutes, and it is never receieved. We have logging in the iOS app and also on the server which indicate that the app is never becoming active and checking in with the server.
It appears to mostly, or maybe only, happen at night. The only rough guess I have is that iOS has undocumented behavior where it will put an app and/or the whole system into a non-listening state if the phone hasn't been interacted with for a long time.
Does anyone have ideas for what the problem could be?
Thanks,
John
