AFAIK there is still no way for a messaging app on iOS to reliably run 24/7. As a result, most messaging apps use their own server for new message notifications

AFAIK there is still no way for a messaging app on iOS to reliably run 24/7. As a result, most messaging apps use their own server for new message notifications. If the app is not running, you get a notification and you can open the app to read the new messages. That of course means a MITM-like server …