I have an "old" flash mp3 player that I just fill up with a pile of mp3 files for exercise. It weighs 70g, can be navigated blind in a pocket, is impervious to

I have an "old" flash mp3 player that I just fill up with a pile of mp3 files for exercise. It weighs 70g, can be navigated blind in a pocket, is impervious to the ways smartphones break (falling damage) and the battery lasts a week. People might also have other motivations, such as wanting to decouple from a service that each week picks a new favorite song to make unavailable.