If we're lucky that's coming soon(ish), they have a project with a German (eco) bank going:

https://www.gls.de/privatkunden/taler

And in a recent interview they said they're in talks with other banks (and also central banks bit they're moving even slower than banks).

I don't think it functions at all currently.

I downloaded the app, there seems to be no way to get any real money into the wallet other than a fake currency for demo purposes.

Makes sense when the version is 0.1 seems to be far off from a production release.

It's a way to digitally pay money like Visa or Paypal but (FOSS and better for privacy), so you could use it for everything from online shopping (micropayments on the fediverse?!?) to paying at the supermarket. If people adopt it ...

I have tried out their Kudos demo, which works great. Otherwise there is sadly not much you can try out yourself yet and self-hosting is a bit complicated from what I have seen in their documentation.