How do iOS app notifications work?

Other p2p apps that I have tried in the past have failed to work on iOS primarily because iOS does not provide a mechanism to keep apps running in the background. Instead, they force app developers to rely on Apple push notifications (APNs) to alert apps that messages have arrived. How does the Jami iOS app provide these notifications? How does this impact its performance and capabilities on iOS devices and the privacy of communications?

In short, Jami uses APN too. But they don’t send messages through push notification, they send empty notification to wake up the app, and the app retrieve messages itself.

Interesting. Thanks for the link!