Zimbra supports all standards like IMAP / POP, CalDAV and CarDAV, so you can easily communicate with other organizations using Microsoft Exchange or Apple's product line. Zimbra can be used with the best e-mail software you like, like Office or Mozilla Thunderbid. But there is also a dedicated Zimbra Desktop application that works in Windows, Mac and Linux. Of course, you can also sync with iPhone, iPad, Windows Phone and Andorid-based devices through the open IMAP / POP, CalDAV and CarDav frameworks.