I have used a dedicated MP3 player during the workout just few years back - I found carrying my entire almost 200g phone during the workout extremely inconvenient.
In the end, I ended that for the benefit of bluetooth headphones which were not supported by the dedicated player.
For running, I got a smartwatch that can store some music locally, so I don't need to be connected to listen. Still not perfect, kind of a hassle to use, and doesn't always work perfectly. Almost miss those tiny iPod nanos. I feel like portable dedicated music players have gone backwards in features and usability with the rise in popularity of perpetually connected Internet devices and streaming services.
Ha, but with that smart watch we have almost came a full circle :)
Except of course, it's multipurpose and I presume much more expensive device now. What's the model?
The Samsung gear watches all support Spotify offline playback. All the wearOS watches support as much local media playback as the hardware allows (I think), but managing that local library is pretty tedious and awful. Especially if like me you either listen through streaming services or streaming from a library of FLAC media on a NAS at home. With the Spotify app on my watch, I just select a playlist to be downloaded while I'm connected to WiFi and that's it. It is not flawless though, sometimes the Spotify database or authentication gets fouled up and you're unable to fix it until you return to WiFi. But I haven't had many issues with it since Samsung switched away from their own bespoke watch OS to wearOS.
Depends on the compression. Yes, you could fit 500 songs on a 4 GB iPod, as the adverts constantly loved to remind everyone about. But it was the early 2000s, so the quality wasn't good, and then we're still talking about a pretty high compression even back then.
Interesting. Most interesting. I take it it would need some soldering? I don't have the tools, but could you send me a video of some instructions on how to do that? Could be a fun future project.