My wife hates running with a full blown phone. She has been using the Ipod a very long time and has gone through a lot of them.
I just paid a premium for a version 8 one as they are something of a collector's item now. I want to try to get her to use something different. Small, light, long battery, blue tooth and can hold a ton of songs.
The Shanling M1 and Cayin N3 are some rather well regarded DAPs (Dedicated Audio Players for those who don't know) right now. I'd avoid anything from FiiO though due to their rough OS designs and half baked features. I have a FiiO X1II, and it's not great. I have a M1 on the way and hopefully it'll be much better. Oh, and all of these options have expandable storage