问题
On Android, to send a notification all you need to know is GCM id of a device you want to notify. Assuming my user knows the id of another user, he sends a message directly to GCM server, what decreases the load on my server. I don't have experience building iOS apps, so I want to know if the same approach is possible for iOS devices. If my user knows id of another apple device, can he send a request directly to APNS?
回答1:
Sending a push is just a matter of posting data to apple servers.
You can do it from your server or the device. It's up to you.
回答2:
Try NWPusher. It contains an iOS demo application that shows how to send push notifications from iOS to iOS.
来源：https://stackoverflow.com/questions/26311306/ios-send-request-directly-to-apns-without-server