You can use the open standards called IMAP and SMTP to synchronise your Zimbra email to your Android smartphone.
Android has several email clients available but we recommend an open source one called K-9, free from the Play store or F-droid.org. Here we talk you through configuring that client but others will be similar.
You are connecting to your Zimbra account via IMAP (to fetch incoming email) and SMTP (to send emails) which allows connection to your mailbox.
To configure K-9 for zimbra ensure you are connected to the Internet then start K-9:
Then select Menu, then Add Account…:
Enter your name, email address and password, then press Next:
Select IMAP account type:
Check the user/password is correct then move to the IMAP server box and enter eg zimbra.opensure.net
Select Security as SSL or StartTLS
Port 993, (leave IMAP Path Prefix as default).
K-9 will now check the configuration before moving on to the outgoing server.
In Outgoing Mail Server section, enter server as mail.opensure.net server then press Next:
Security is StartTLS if available and the port should be 587 (not 25).
Authentication should be PLAIN and the user/password should be the same as for IMAP.
Click Next and wait until it has finished verifying configuration.
Give this account a name that makes sense to you, eg Simon’s OpenSure Account and then give the name that shows when you send message eg Simon Sayes.
Then click Done and the account is ready for use.