-Make sure, in ZCS Admin, that "mobile" feature is enabled for the user in question, either directly or via COS
-on iPhone, Settings, Email account, New Email Account, "Microsoft Exchange"
-enter email address, username (no domain needed), password, and press Save/Next (forget which)
- after about 10 seconds, you will be prompted for a server name... enter it (FQDN)
-if it successfully contacts your Zimbra server, you will be presented with the option to sync/not sync Mail, Calendar, and Contacts |