I'm not a Starbucks regular so I may have missed a detail. Transferring money from a stored bank account to the app seems to be a server action, so the server should be doing the auth. What then is the point of storing the password on the client? If it's just to confirm possession of the phone, a token would be better for usability, as well as in all the other ways a token is superior to a password. TFA says the password is also used to activate the app, but a token signed with a timestamp and emailed to the user would be better for that.