The Google Site Verification Python Sample Code by Google presents API interaction using HTTP format and OAuth2 authentication. Developers can integrate validation of sites and domains with additional APIs that provide similar callbacks.
Google Contacts API gives client applications access to a user’s contacts list where the application can create new contacts, update or delete existing ones, or query for contacts that match particular criteria. This tutorial explains how to implement the API in C# and ASP.NET with OAuth 2.0.
Last week Facebook rolled out several platform updates pertaining to Authentication, Social Plugins and the Graph API. Several key features were added to the platform; introduction of a new access token API endpoint, the launch of the Shared Activity Plugin and real-time update settings were added to the App Dashboard.