https://subjc.com/castro-playback-scrubber/
Castro is an exercise in bold restraint. It eschews buttons whereverpossible in favour of gestural interactions allowing the screen deferto the content, rather than the controls.
Castro is my go-to app for playing podcasts and I use it literally every day. This article shows the ridiculous amount of thought and hard work that goes into creating just a tiny, but crucial, part of the app.