It seems taking users out of your app / off your website to sign up or purchase something would be detrimental to conversion rates. (I don't know about you, bu

It seems taking users out of your app / off your website to sign up or purchase something would be detrimental to conversion rates. (I don't know about you, but I can't think of anything more distracting than my email inbox.) I know it's not popular on HN, but we already have a simple method that removes passwords: OAuth.