I think most of us use Bluetooth these days. I actually own an iPod Classic with RockBox and quite a few audiobooks loaded on, but of course it can't really compete with the Audible/Libby workflow on my Android phone.
When I'm not able to have an ebook in my hand, I listen to my audiobooks pretty much all the time. That includes my daily 20 mile bike commute
I've used earbuds with this funky technology called "bone conduction" for years and years. Shokz makes the OpenRun model, and it's pretty much the best out there. I can hear traffic (heavy, and through huge streets, have to keep present) and still know who said what and when!
Plus, they're waterproof, so I can wear them swimming!
Cheers. -tb