I need a good portable music player, so I don't rely on my phone for audio. I already have a quad-driver IEM, hence a good one with a good card is necessary. I will definitely buy it used, so make sure it's affordable and under 100 Euros. For products over 100 Euros that are worth it please mention why.
Folks used to like Rockbox (
https://www.rockbox.org/), runs on a variety of players.