I'm building ntfy [0], an open source push notification service with a dead simple REST API. You can basically push messages to your phone via curl or any script. No sign up, no cost, no API keys.

Motivation is: I always wanted it and it was fun to build. I since learned Kotlin (for the Android client), Swift (for the iOS client), and React (for the web client). It's awesome to learn so many technologies. Fun!

[0] https://github.com/binwiederhier/ntfy