There are a few things in a search for “social media” where tools sometimes get mentioned, but it’s good to try to coral people’s ideas here in one topic. 
At one point (circa 3 years ago) I was generating audiograms to publish to Instagram for the Movers Mindset podcast. That’s an audio-only podcast so not exactly what you’re asking about in your second question. We did some of them by hand (probably using Apple’s iMovie) and we did some with… ugh, actually I can’t remember. It took an audio clip (mp3) and laid transcription on top of a static image.
They used to have play-counts ~10x the number of likes we were getting at the time. Of course, that’s apples-n-oranges; views are automatically started (unless one disables autoplay) and likes require user action. I never got the impression they were hugely better for us. …mostly because I’ve never had a clear model for what any social media was actually supposed to do for me/my-shows. [another discussion altogether]
Social media came up in our most-recent Oct 29 Campfire too. We were discussing more like what to do with social media, than how to make the social media assets for posting.
All of which reminds me that I wanted to post a topic about some of my thinking around ‘what to do with social media’ or ‘whats the point’…
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