SAN FRANCISCO—Microsoft Cloud and Enterprise Corporate VP Scott Guthrie had more than 40 new features from Microsoft’s cloud platform to talk about during his portion of the second-day keynote at the Build developer conference. Among them were a few announcements about Active Directory and Office 365 that could boost enterprise mobile application development using the Azure cloud—for Apple iOS and Android devices.

Guthrie announced that the Azure cloud will now provide authentication services for applications based on Active Directory using the exchange of OAuth tokens, which will allow Web applications in the cloud to use enterprise or Office 365 credentials to authenticate users. These features work with Active Directory Free, now a free component of the Azure cloud service.

The capability requires companies to use the Azure Active Directory service either as their primary Active Directory instance or through replication from their onsite servers. “All 300 million users in Azure Active Directory today, and all the enterprises that sync with it, are now available [as potential customers],” Guthrie said.

The hooks will also allow Web applications to reach into Active Directory-enabled applications, such as Exchange and SharePoint. But these tools aren’t just limited to Web applications; Microsoft is also providing an Active Directory software developer kit and Office 365 software programming interfaces for iOS and Android applications as well.

Grant Peterson, the chief technology officer of the “digital transaction management” software developer DocuSign, demonstrated using his company’s iOS application on an iPhone to authenticate with Active Directory and sign a document pulled from a SharePoint workflow onscreen. He then published it as a PDF back to the SharePoint server.

Microsoft also announced the general availability of Azure Active Directory Premium, a version of the cloud Active Directory service that gives IT departments a greater level of reporting and control, corporate branding of the service, group-based access control to software-as-a-service applications, user self-service password resets and group management, and multi-factor authentication for Microsoft and third-party cloud services.