New Security Measures Will Affect Older (non-OAuth 2.0) Applications - Google Developers Blog
Apr 23, 2014

Summary
This post announces the deprecation of older authentication methods (non-OAuth 2.0) for Google APIs, emphasizing the security benefits and broader compatibility of OAuth 2.0. It provides a timeline for the deprecation and directs developers to resources for migrating their applications.
More from the Federated Login and Identity Management trail
- Enhance Security and Trust: New Session Metadata in Sign in with Google- Google Developers Blog
- Supporting Google Account username change in your app- Google Developers Blog
- Usability and safety updates to Google Auth Platform- Google Developers Blog
- Chrome on Android to support third-party autofill services natively- Google Developers Blog
- Federated Credential Management (FedCM) Migration for Google Identity Services- Google Developers Blog