GPlay Music is a wrapper of the Google Play Music web player which supports mac's media keys(play, pause, next).
I built the app to add media keys support in the web player. I can now use the play/pause and next buttons to control the Google Play Music player.
I mostly do iOS development on a day-to-day basis, so this was an opportunity to experiment a bit with macOS development. I specifically played around with the WebView component and I can imagine how powerful it can be since it's basically a full-featured web browser.