Libby is a free and legal app for your phone.
You sign up using your local library card and there are loads of free Audiobooks, as well as eBooks too.
Audible is great too - sign up for £7.99 a month which gets you 1 credit per month. Quite often they have a 2 for 1 offers too.
I use Audible, there is usually a free book sign up offer, the downloads are pretty easy to do too.
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