I think right now their demo is using QR codes. I don't think the jump from QR to NFC is that difficult but I could be wrong and I don't know what their pipeline is at the moment.

You could look at the Taler Project. It is still probably years away from becoming usable but it is a really interesting and promising payment system.

The docs are outdated. They are currently releasing once a month. There is an issue on their github here to update the documentation