Not as sophisticated as what @phf is talking about but I recently made two new little jingles for my podcast. The first one was created using my favourite app on the phone, PixiTracker.
https://alexschroeder.ch/podcast/jingles/jingle-50.mp3
https://www.warmplace.ru/soft/pixitracker/
The other one I recorded after random fiddling on the machines…
https://alexschroeder.ch/podcast/jingles/jingle-51.mp3