One cool development in the past year or so are hardware trackers. Basically trackers for the DAW-less crowd. The polyend tracker [1] is really nice and a great value. And I'm super excited for the dirtywave m8 [2], kind of like a supercharged hardware LSDJ [3] (which is also a great project). Starts shipping in the next month or so, but you can already try it with publicly available firmware using just a teensy 4.1.

Back in software, can't help but mention Sunvox [4]. Not exactly the same niche as Renoise (which aims to be closer to a traditional DAW), but it's an excellent modular tracker that runs pretty much anywhere, free (as in beer) on desktop and cheap on mobile. It doesn't have any support for VSTs but comes with a nice set of synth and FX modules that can be connected and bundled into "metamodules".

[1] https://polyend.com/tracker/ [2] https://dirtywave.com/ [3] https://www.littlesounddj.com/lsd/index.php [4] https://warmplace.ru/soft/sunvox/

I know what a DAW is since I use Logic Pro X, but what is a tracker? What are they good for?

[1] https://en.wikipedia.org/wiki/Music_tracker [2] https://github.com/steffest/BassoonTracker