Exchange ActiveSync

Exchange ActiveSync (commonly known as EAS) is a designed for the synchronization of email, contacts, calendar, tasks, and notes from a messaging server to a smartphone or other mobile devices. The protocol also provides mobile device management and policy controls. The protocol is based on XML. The mobile device communicates over HTTP or HTTPS. Originally branded as AirSync and only supporting Microsoft Exchange Servers and Pocket PC devices, the protocol has since become a de facto standard for synchronization between groupware and mobile devices.

Microsoft licenses the technology. Support for EAS is now implemented in a number of competing collaboration platforms, including GroupWise with the Novell GroupWise Mobility Services software and Lotus Notes with IBM Notes Traveler. Google previously offered support for the protocol for personal Gmail and free Google Apps accounts, but began removing support from all but paid Google Apps for Work subscriptions in 2013. Beyond on premises installations of Exchange, the various personal and enterprise hosted services from Microsoft also utilize EAS, including Outlook.com and Office 365.

In addition to support on Windows Phone, EAS client support is included on Android,iOS,BlackBerry 10 smartphones and the BlackBerry PlayBook tablet computer. The built-in email application for Windows 8 desktop, Mail app, also supports the protocol.

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