What’s the best way to listen to audio books using Jellyfin on iPhone?

[Reken]

I’ve used the Jellyfin app and it’s really finicky. Swiftfin, Finamp and Infuse don't even display my audio book library. Is there another way to do it that I’m missing?

[TheDreadPirate]

I am assuming you are using the Books type library for your audio books. Which is what you should be using since the Music library doesn't support playback tracking/resume. Those clients do not support Books libraries.