Zimbra email collaboration has more than 400 million trusted users worldwide. It is the leading open source enterprise email solution and the most preferred alternative to Microsoft Exchange.
Zimbra Includes email, contacts, calendar, documents and more. It is a Web-based application suite that can be deployed as an on-premise private cloud or outsourced public cloud service.
It is compatible with desktop email clients, such as Windows Outlook, and is compatible with Windows, Apple and Linux computers. It also performs over-the-air sync to mobile device operating systems, including iOS, Android and Windows Mobile.