More importantly, how to at the same time make payment as frictionless and password-free, so that you do not lose any business to people having second thoughts

More importantly, how to at the same time make payment as frictionless and password-free, so that you do not lose any business to people having second thoughts or going to competitors! Because that is the purpose of a smartphone - to funnel the user's money to the true owners of the phone. Any barriers to that must be removed.