How to detect if an email is a Google Account?

Question

Me and some guys here are working on an start up. We are currently using Google OpenID API to manage registration and login to our app, but we want to migrate to a easier user r

Answer 1

You cannot do that. I don't think Google could tell you that without user consent.

You could, however, see if the domain is a a Google Apps domain by use this as the Discovery URL: https://www.google.com/accounts/o8/site-xrds?hd=mail.moztw.org

Noted that the admin of the domain might not properly installed OpenID support for the domain. My slide have discussed this in detail: http://www.slideshare.net/timdream/google-apps-account-as-openid