You can use our new beta service to sync your device eg smartphone, tablet etc using Activesync with our Zimbra 7+ service.
We deploy a Z-Push service to do this for you and as a result only three bits of information are needed.
1) Activesync server = https://z-push.zimbra7.opensure.net
2) Username = your email address or alias
3) Password = your normal email password
This allows you to use any standard Activesync client to synchronize email, contacts and calender to any number of common mobile devices including iPhone, Android and even Microsoft including Windows 8 devices.
Some clients will require additional information such as the preferred email address and other specific information that it may use but the above information is common to all.