Hmm, I could be in the market for a new bank a bit later, but what isn't clear on your website is whether the app is mandatory, or the functionality is available trough the web browser? (PWA or WASM binary would be OK, I guess?).

I'm using N26 right now, but I have since stoped using closed-source software altogether on my phone, and will likely switch full-time to a pinephone. One of the things that irks me is that multiple services require 2FA trough their proprietary app or SMS rather than TOTP or FIDO/Webauthn/other security-token based tech. Not sure if that's for legal reasons? In any case, that's my number one usability issue with other banks.