I have a large ~30Gb backlog of podcast episodes that I am slowly working my way through. Currently these are stored in iTunes and I occasionally sync an old iPod Classic to get new episodes and delete the episodes that I have listened to.
I would like to move to one of the iOS apps such as Instacast or Downcast so that I only have to carry a single device - my iPhone - around with me for my audio needs. I would like to be able to listen to the backlog of episodes as well as download new episodes, ideally in the same feeds. I am guessing that I would have to move my podcast backlog to cloud storage and set up some kind of feed to one of these apps, although I don't see this listed as a feature of either.
What is the most sensible way to achieve this?