http://collect.readwriterespond.com/kind/audio/feed/
However, you can also make a feed from a tag or category:
https://collect.readwriterespond.com/tag/microcast/feed/
I also syndicate to Huffduffer. This can be used in regards to podcasting apps.
In my exploration of Anchor 3.0, it would seem that you can only download audio recorded in the browser. You cannot download audio recorded on mobile.