Audio has been around since, I suppose, the spoken language. The difference now is distribution and availability. Audiobooks, podcasts, smart phones, voice controlled home speaker systems, connected cars, and who knows what will come next.
There are so many podcasts to be a guest on! How do you choose which ones are a good fit? Introducing Listen Notes. https://youtu.be/DFHEJDMktUk
This is where things can get exciting with your book as a podcast as opposed to (or in addition to) an audiobook.
Bradley Charbonneau is an “unstoppable writing machine.”