FREE from your public library is best for sure.
I use the IOS Libby app, though there are others that are similar.
I’m with Calgary Public Library quite happy with the selection. I can get almost any book I want — though sometimes I’m on the waiting list for a couple of months.
I gave my library a big donation in 2020 as I was using the service more than ever.
Audible.com by Amazon is the market leader.
I’ve bought hundreds of books over the years. They have a better selection than my library and there’s no waiting.
That said — I’m thinking of cancelling Audible next time round. Prices have never gone down and they’ve not innovated much in all the years I’ve been paying my subscription.
IF dying to get an audiobook right away in future, I’ll simply buy it.
I tried Scribd. Didn’t like it enough.
MIGHT try Audiobooks.com, another Audible competitor. But it’s the same price, same benefits, so I’ll probably cancel after my free trial. AND I hear unused credits expire in only three months. No go.