If a phone has turned off receipt of remote push notifications, or a push notification fails to be delivered, can the originator of the push get informed that it failed to be delivered?
I know there is the feedback service available to query for failed delivery attempts, but that sounds like its a pull type feedback rather than something like a receipt sent for every push notification.
So suppose we sent push notifications to 100,000 devices, could we then connect to the feedback service and see which ones failed? How accurate is this, is there a time delay before feedback info is available?
You can’t tell if a push has been delivered.
The feedback service is designed to inform you of devices which have failed to deliver pushes for some time. You should act on the data in there and stop sending pushes to that device. It could take time to get into the feedback service though because it’s only really meant to go in there when Apple have deemed that the device has uninstalled your app, or the device is no longer used, or a similar event rather than just the device is out of range at the moment and has no connection to APNS.