We got my daughter a Yoto and it's a great device. She sticks a card in and it plays music or an audiobook. There's a "screen" but it's a low resolution pixel grid that shows pixel art of the current track.
We use luuni which is similar (except that it also enable choose your own story with audiobooks). Even then, we limit it because otherwise he would want to listen to it every time before sleeping (and it prevents him from sleeping)