Google Add-ons

Google Add-ons are mini apps that can be added to certain Google Apps -Google Docs, Sheets, Forms, etc.- to enhance the functionality through adding new features that target specific needs. Add-ons are mostly free (there are occasional "freemiums" where features you may desire require a paid account) and can be found in the menu under Add-ons of all the Google Apps.

Here is a link to Google support page that covers how to install/uninstall Add-ons.

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