Comment on ntfy.sh | Send push notifications to your phone or desktop via PUT/POST
oh i really use it for notifications for schildichat from my own matrix-server. so i need no other notification-provider.
and i build a little monitoring with it for my private servers. Every time a server crashes, i get a notification on my phone. are the crashes annoying, i have to improve my services. :-)
or think about some service, which puts out a pdf, you need. let's send this directly by notification...