Official Google for Work Blog: Google Apps identity, easy and secure single sign on for popular work apps

Also see Google Brings Easier Identity Management to Non-Google Apps (Fortune), which notes "Microsoft already offered similar single cross-vendor login schemes via its Azure Active Directory service. Thus, Google’s latest move looks to be another shot in a continuing battle for the desktops of business users, with Microsoft Office leading among big companies but Google Apps for Work making a strong play with smaller businesses."

"Last year, we announced support for SAML 2.0 where Google is the identity provider. Today, we're adding pre-configured support for Microsoft Office 365, Facebook at Work, Panorama9, New Relic, Concur, Coupa, Box, Slack and more. This adds to the hundreds of apps we already support through the Google Apps Marketplace and OpenID Connect.

Google's identity services provide even more security on mobile when combined with Google Apps enterprise mobile management controls like password strength, lock screen requirements and app management. These can work in tandem with the increasing number of mobile security options, from hardware such as fingerprint readers, to software such as Google’s Smart Lock. Our Google Smart Lock features are available to all Google Accounts, including those used at work, and we provide identity services and enterprise mobility management (EMM) as part of Google Apps for Work at no additional cost."

Official Google for Work Blog: Google Apps identity, easy and secure single sign on for popular work apps