Google Sign-In is a secure authentication system which reduces the burden of login for your users, by allowing them to login with their Google account. To sign users into an app that integrates Google+ features, Google Sign-In helps with social scopes
Google Sign-In increases conversions by reducing the burden and friction of login. Ecspecially for mobile users, all while helping users keep their accounts secure. With minimal effort, user can add a trusted registration system that's familiar to users and consistent across devices. Google Sign-In lets users skip high drop-off registration forms and avoid having to remember yet another username and password. This makes registration faster and more secure, and reduces support costs for forgotten usernames and passwords.
By requesting social scopes through Google Sign In, your app can provide a social experience for your users through the use of the Google+ Profile and Social Graph APIs.
