Also worth mentioning I think this is exceedingly useless for SMEs that aren’t single-person businesses. I don’t think that they’re going to log in with their Stripe/Square account on staff devices and there’s probably not money to buy an iPhone vs just renting a terminal for some money
However, if there’s something for the industry like a software as a service provider that can white-label an app with proper staff login w/ correct non-repudiation impl. then actually, yeah that could be super super transformative