The some functionality between Yathit Chrome Extension and Yathit Gmail Addon are overlapped, but they are completely separate products developed by different technology stack. Yathit is committed to support both products.

Gmail Addon is build using Google App Script and run on Google server. Chrome Extension is run on your browser using standard HTML, CSS and Javascript. Chrome Extension enhance Gmail UI and often have to hack into it and sometimes unreliable. Gmail Addon is reliable but slow due to running on server side. Gmail Addon cannot interface with Gmail UI and only show on message view.

The following table shows major functionality available in each product.

Function Extension Addon
View customer information
Save email and attachment
Create, edit, relate record
Sync calendar
Work with internal CRM
Work in Gmail Mobile App
Work in mobile browser
Work in all desktop browser
Cost per user per month 9 $ 9 $

Even when both offer same functionality, such as saving message, the option and user experience are very different. You may have to use both products.