Synchronizing event across app users

Hi all. I'm trying to have an AHAP file start playing simultaneously for all users. My initial thought was to use a push notification to trigger this event, but not everyone receives it at the same time. Another idea is to use an HTTP server and livestream data. I would greatly appreciate any input or suggestions on how to remotely synchronize an event for all app users.

Synchronizing event across app users
 
 
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