I followed http://googlemac.blogspot.com/2011/05/ios-and-mac-sign-in-controllers.html to allow users to use Google to login to an iPhone app. After I tap \"Allow access\" bu
When using gtm-oauth2 to sign in to Google services, be sure the Google API Console project registration shows in the API Access section that the Client ID is issued for an installed application. This is described in the gtm-oauth2 documentation.