So roughly speaking this is WebAuthn for a web site, with the iphone acting as the dongle. It's a really good idea. I can see there being a big demand for just simplifying signin - I can easily see a time where it is worth not having the hassle of managing multiple signin processes and just choosing webauth or nothing. Edit: to be clear this won't affect B2C sites whose monetisation is based on getting as many people…
No need to speak roughly.