Yes, you can synchronize emails between Gmail and Zoho CRM.

To synchronize Gmail with Zoho CRM, you need to first configure a POP account in Zoho Mail.
Here is how you setup a POP account in Zoho CRM.

Zoho Mail (http://mail.zoho.com) seamlessly integrates with Zoho CRM, and Zoho Mail supports POP access. Once you configure POP, you can easily fetch emails from Gmail to Zoho Mail and in turn Zoho CRM.