Smart speakers are getting more and more popular, but for the most part podcast listening is not the MAIN thing that people are using their devices (like the Amazon Dot, or Echo) for (and we can include the Google Home).
There are companies that will charge you a monthly fee to host your podcast and distribute it to Amazon. Currently, I don't recommend that as according to Libsyn, .2 (not 2 – point two) percent of people are listening to a podcast on smart speakers and set-top boxes (Apple TV, Roku, etc).
So while it is the new sexy thing (and there are always exceptions to the rule) I would focus on listing your show in the directories before worrying about smart speakers.
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