Spent a solid hour trying apps to switch to. Found podcast republic which does everything I want with tons of customisation and a one time payment to ditch the ads. Love it.

Yep, I don't use all of those features so I had a quick look and yes it has all of those.

If it's a really old and/or dumb system, maybe. Basically if the card is just giving a number when you can it, then it should be possible. But if there is any level of processing happening on the card (which is generally the case, usually some kind of cryptographic call and response) then you're not going to be able to add it to your phone without more work than it is worth.

You'll need to look up what technology your transit system uses. Sometimes Wikipedia has this information. Here is an example, the UKs Oyster Card https://en.wikipedia.org/... Once you know the technology being used you can start googling to see if it's cloneable.