It's a Creative Zen Stone that I got as a Christmas gift in 2008. I just found it in a drawer, and it's still holding charge. The last thing I put on it was The Life And Times Of Scrooge by Tuomas Holopainen, in 2015 -- I don't know why, at that time I definitely had a smartphone.
It has a headphone jack, which immediately makes it better than every smartphone produced in the last several years, and it can easily drive my 80-ohm Beyerdynamic. The audio quality is as good as one can expect. The only drawback is that it only holds 1GB... my old CD rips had to be compressed to hell and back.
Let me reiterate that this has been sitting untouched for a decade and was immediately ready for action. No login, no annoying software updates, expired subscription, or remote bricking by the manufacturer. Eat my shorts, Spotify Car Thing.
P.s. A Lifetime Of Adventure is a banger. https://www.youtube.com/watch?v=JWwSVOo5K_k
I started using something similar recently. I started buying music on indie sites and I have a closer relationship with my music. I keep listening to the same things since my library is still small. Because of that I remember the lyrics, know the names of favorite tracks or hum the songs during the day.
With phones not having the 3.5mm jack these days it sort of makes sense to have a separate 3.5mm jack device even.
The one I got is a Fiio Snowsky Echo Mini (2025) that is similarly old school - no Wi-Fi, just USB file transfer upload. Listening to music on a smartphone is mentally draining in comparison.
The player Is not such a good deal as it was before the Fiio tariff-related price hike, when it was around 40€, but eh. The battery is soldered on despite the case having a "stylistic" battery cover on the case. Supposedly on the inside it's still a standardized battery cell, so if you unscrew the case it should still be serviceable.
There are MP3 players which are simple and Digital Audio Players (DAPs) which are supposed to be more hi-fi. In Europe, AGPTEK is available (can't vouch, but see A52PL, C2S, U5PL) too. In the US, a simple modern iPod clone seems to be the Innioasis Y1. SanDisk (Western Digital) seems to have stopped making their Clip line and they're hard to find used where I'm from.
There's also a custom firmware for some DAPs/MP3 players called rockbox, here's the supported device list https://www.rockbox.org/wiki/TargetStatus