https://www.taler.net/

"privacy friendly online transactions"

I came across this and it's looks interesting it seems to have been out for a while and seems to work well in the demo.

it sounds a bit like Blockchain, but it doesn't seem to be. which i would think makes it more appealing because the setup was easy... but i can't find any examples of it being used in the wild.

i was expecting to see more cases that used it when i saw there is funding for it from https://nlnet.nl/

i think this could be good to add into my app. but i wonder if it might not be a good idea if it hasnt established itself as reliable in the wild.