ILikePigeons

PBZ.hr

edit: it does seem to support card readers, however, I have no idea if that method would work on Linux.

Nope, only the banking app can be used to generate the code.

There are a couple of issues with that mentality, there are some countries in which money transitions almost entirely revolve around proprietary apps and services, Sweden for example (a decent article that talks about Sweden in particular). In my country, I can't find any public information on which banks require apps and which don't. The bank that I am currently using does have a website, but I have to login with a one-time password generated from an app. Also, going to a different bank assumes the same bank won't do the same and exclusively require an app down the line.

Yup, privacy (and many other things) should be done to ones ability and not to ability of others.