Some info in case someone is on the fence about this, and are living in the UK. I use Monzo, and that works perfectly on GrapheneOS.
If they ever stopped working, I would just CASS to another bank. A bank that has a posture that something like GrapheneOS is too insecure to use their app on is a bit of a red flag.
If they ever stopped working, I would just CASS to another bank. A bank that has a posture that something like GrapheneOS is too insecure to use their app on is a bit of a red flag.