It is not free or open source but is software. FWIW I use it and like it. It’s a one time fee and not a subscription service. The fee is under 10 USD. The program requires minimal permissions and doesn’t even ask for (I.e. opt-in) for much more than it really needs to run. I find it relatively intuitive and it works with android auto which is something I really want in a media player/library at the moment.