Is there a good replacement for Growl/Prowl?

I use an app called Pushover which has apps for the Mac and iPhone/iPad. It can receive messages of various levels of “urgent-ness” even to the point of being allowed to bypass “Do Not Disturb” on iOS 14 if you so choose.

Pushover has an API that allows you to send messages using curl and it is very easy to use, and has very generous usage allowances. Using curl also means that it should work from a Raspberry Pi or any other Unix-y system.

The iPhone/iPad app, Android app, and Mac cost $5 each (iPhone and iPad is a single $5 purchase, Android is $5, Mac app is $5). These are one-time purchases, not subscriptions.

This is a service I had used since 2014 and found to be extremely reliable, easy to use, and inexpensive. I highly recommend it.

I wrote up an example shell script to show how to use it, which I call po.sh (for pushover obviously).