It’s got an open API so really there’s a lot more than my own use case.
I’m using it right now for getting notifications from flows in ActivePieces (I don’t want to get spammy with my site, which is the link in the original post, but there’s a how-to on getting that up and running also… ActivePieces is like a self-hosted Zapier)
Think of it more like a push notification server than a messaging platform. You would need a service that sends push notifications to Gotify topics. I get the sense that under the covers it works a lot like MQTT where you have apps publishing messages to topics, and you have consumers (in my case, iGotify app on iOS) that pull those messages off the topic and present them to the user as push notifications.
Though… I think I need a better iOS client than iGotify. It’s not actually giving me any push notifications so it’s missing the whole point for me.