This reads a lot like simply another way to tie users up into a smartphone specific Eco-system, not to mention the privacy implications. There is a much better

This reads a lot like simply another way to tie users up into a smartphone specific Eco-system, not to mention the privacy implications. There is a much better approach that doesn't have the privacy problems that the proposed solution has: https://certisfy.com https://certisfy.com Use good old PKI with the verification process for generating certificates delegated to suitable third-parties.