My bank unfortunetely requires the app. I could use a tan generator, but that would cost me money and wouldn't be as comfortable as the app, I couldn't also use it with my VISA card, which would mean additional costs for the other card.
Or maybe I need to change my bank? Or use my iphone as a verifier, it seems to still work for that purpose. However, when travelling it's not that flexible.
Even if I would create an google account and download the apps I need to delete my google account wouldn't make any sense, because of app updates - if even possible.