First of all, you will have to look in the App Store to find out which podcatcher apps, if any, are available for iOS 6.1.6.
It used to be possible to find out which version of iOS an app required, but that functionality has been removed, so I can't tell which apps will run on your version of iOS. Even if I use my desktop to look at my preferred podcatcher app or its website, there's no way to tell whether there's a version for iOS 6.1.6.
So check the App Store from your iPod.
If you find Podbean, I recommend that you give that a try. If not, can you find one that will work on your iPod?
Don't pay for one, or at least, not without trying it first. All Podcast apps I have tried have their weaknesses. I've yet to find one that doesn't, so you could end up paying for a piece of rubbish.
So, back to Podbean, which I use. The free version is ad-supported, but the ads are not intrusive. By the way, I receive no compensation of any kind for recommending Podbean (see my what I don't like comments, below - I doubt they would want to reward me after reading it).
What do I like about it?
- It's better than the Apple Podcasts app, by a long way
What I don't like:
- Suggestions for features are prioritised if you pay their yearly subscription fee, over those who don't pay. So users who have enough the experience of the app to be able to come up with useful suggestions are put to the bottom of the list over someone who has listened to one show, but coughed up their fee in order to get their half-baked ideas prioritised. (Object lesson in "how not to run a business")
- My suggestion to add an Android version feature to the iOS version resulted in the exact opposite: to remove the feature from the Android version (which I now use). Their explanation, when they wrote back to me about it, left me dumbfounded. The only way I can explain their thinking is that it's like the child on its first bicycle ride who manages to get as far as, and crash into, the only lamp post in the street. In other words, you simply wouldn't believe it's possible
So, a warts and all review.