This add-on will load a sidebar menu for you and you can then begin to set up notification rules on your Google Sheet. You can add as many rules as you like and the add-on will keep a track of them. You can track single cell references on a worksheet called ‘Notification Rules’ and you now have the option to track across Rows or Columns entirely. You can view these three worksheets and even amend the rules directly on the sheet. Once the spreadsheet is changed and the values reach the notification rules you have set you will automatically receive an email to inform you. You can also add multiple email addresses to one notification rule simply by separating them by a comma. You can also use Slack notifications instead of emails if you prefer.