"I have assumed that this is to allow the banks to track what you do beyond what can be done in a browser."
Because access to all your financial information, your address, phone number, ability to crush your credit score, holding all your money, your mortgage, knowing your location via your purchase history, knowing your purchase history - all that is fine, but tracking you on your phone? That's the line!
Not tinfoil hat enough mate. You need to be stuffing your gold reserves under your bed.