Is it still possible to use Google OAuth without plus?
google-plus, php
Solution
You can use Google OAuth as a mechanism to authenticate users without requiring that those Google users have activated Google+ accounts. See Using OAuth 2.0 for login. This approach relies on requesting the user's identity via the `userinfo.profile` or `userinfo.email` OAuth scopes.
You get advanced functionality and social capabilities if you use Google+ Sign-In, and if your users opt for that option, they will be prompted to upgrade their Google account. This approach uses the `plus.login` OAuth scope, which gets you identity information in addition to other API methods that can be called.
Choosing the approach that works for your app and audience is up to you.
Problem
I have a working php code which lets users login through Google Api. The problem is, this code requires users to become Google Plus users. I use the latest api located at http://code.google.com/p/google-api-php-client/downloads/list and still couldn't find out if I can use the same service for people who do not have and do not want to activate Google "plus". update: I understand that this might be a 3rd party api question and I also think that this is a question about a popular 3rd party api and this question and it's answers may still help many people out there. answer of the question: for quick reference, the answer is *Google_Oauth2Service* class