alt Hacker News[citation needed]
I run GrapheneOS and use several US-based banking apps. I'll not name them since I don't really want my HN account associated with my financials in any way, but I've got a mix of well-known national bank apps and smaller local credit union apps working.
I'll admit there is a single institution's app I've found that doesn't work, but that is just one of several that I use.
For me, the showstopper would be NFC payments. From what I understand, Google Pay doesn't work on Graphene. I have all my credit cards in GPay, as well as a transit card. I use it for boarding passes when I fly, and any other tickets/passes that support it, since it tends to be much more reliable than the airline or ticketer's app. I've come to heavily rely on it, unfortunately.