Bulk email system in without any extensions and without using third party website
By using airtable i maked it
1)take spreadsheet in your customers project and store your customers email according to their category in different columns
2)at the time of storing email use join block like this use comma block to store email
3)then call data from spreadsheet in admin app and show it in a textbox and use activity starter to open gmail app
4)when data called the emails is between brackets remove brackets and click on send button done your gmail opened with selected emails
Remember google has certain limis to send emails in 1 hour or in 1 day.
