No ‘normal user’ is knowing that. You are a Android profi and for you it will be easy.
And I’m allways telling: Do you have your high security documents allways in your pocket ? No, you have them stored in a safe.
So why using your phone as a safe ?? It’s only a PHONE !!!
But I will stop the discussion here, because the user want’s know about banking apps. So this discussion is out of topic.