For all the "My Banking Apps don't work", I'd raise one question: Do you really need access to banking apps on the go? I get that it can be handy and maybe you legit do, but I'd wager most people don't really do. If you can pay by phone you can pay by card and the card has less potentially to weirdly break. And if your bank demands a phone app to be used, you can always have a cheap stock android lying around at home…
In the UK at least, banking apps are how you give people cash when you owe them for dinner, drinks, whatever. It's also needed to authorise online payments. And for travel, location services is often used by the better banks as an alternative to immediately blocking your card every time you go anywhere. Then there are account perks[0] like airport lounges, co-working spaces, exercise classes, etc. that all use the ap…
I routinely use my (U.S.) credit card abroad and never had issues. I don't have any banking app on my phone, which runs Graphene, because I do not need access to banking on the go. Things such as airport lounges, co-working spaces, exercise classes, may be valuable, but none of these things is more important than my freedom. I do not tolerate the thought that some company may track which services I use and where I go without my consent. I therefore do not use proprietary apps on my phone. If something does not work in the browser (Vanadium), I will do without it.