This article was published in 2017 and updated in October 2026.
Google Docs and Google Sheets are powerful on their own, but add-ons make them even more useful. Just like extensions for Chrome add features to your browser, add-ons extend Google Docs, Sheets and Slides with tools for approvals, mail merges, citations, diagrams, signatures and much more. Here’s how add-ons work and how they can help you — especially with document approvals.
What is an add-on?
An add-on is a small app from Google or a third-party developer that runs inside Google Docs, Sheets, Slides or Forms. Add-ons are distributed through the Google Workspace Marketplace.
How to install an add-on
- Open a document in Google Docs (or Sheets/Slides).
- Click Extensions → Add-ons → Get add-ons.
- Search for the add-on you need, check its reviews and requested permissions, and click Install.
- Afterwards you’ll find it under the Extensions menu or in the side panel.
In a company or school account, your administrator may control which add-ons are allowed.
Document approvals and workflows
Many documents need sign-off before they’re final: a supervisor approving a report, a principal checking a policy, a manager signing off a budget. A workflow is a series of steps involving two or more people. In a sequential workflow each step depends on the previous one; in a parallel workflow several reviewers work at the same time. Workflow management software automates these steps.
When we first wrote this article in 2017, add-ons such as Collavate brought approval workflows into Google Docs and Sheets, with parallel and sequential reviewers and approval tracking. Today, many Google Workspace editions also include a built-in Approvals feature in Google Drive, Docs, Sheets and Slides: you send a file for approval, reviewers can approve or reject it and leave comments, and the file is locked against changes once approved. Some editions also offer built-in eSignatures. Add-ons are still useful for more complex, multi-step workflows.
Benefits of approval workflows
- Everyone knows which version is the approved one.
- Managers can see the status of approvals at a glance and spot bottlenecks.
- Reviewers can comment, accept or reject without long email chains — useful when team members can’t meet in person.
- A record of who approved what, and when, helps with company processes and audits.
Other popular types of add-ons
- Mail merge: send personalised emails or letters from a Sheets list.
- Citations and bibliographies for students and researchers.
- Diagrams and flowcharts, for example from Lucidchart or draw.io.
- Translation, grammar and writing tools.
- Data connectors that pull information into Sheets from other services.
A word on security
Add-ons can access your documents and sometimes your email, so only install add-ons from trustworthy developers, check the permissions they request, and remove add-ons you no longer use via Extensions → Add-ons → Manage add-ons.
jack buck
Oct 22. 2020
“Thanks designed for sharing such a pleasant thought,
paragraph is fastidious, thats why i have read it entirely”
Harold Burton
Jun 03. 2021
My favorite Chrome extension is unpinterested! When searching Google for images, I don’t want to see Pinterest images. If I wanted to see Pinterest images, I would search Pinterest. An added bonus is when searching Google for ANYTHING, the results don’t include Pinterest.
Ashley Jones
Jun 18. 2021
Lol, these arbitrage opportunities is why Amazon’s share price and PE is completely inflated at a 270x PE. Using investor’s equity to fund a loss on every textbook trade? Spencer you’re just going to cause the acceleration of the financial correction on Amazon’s share price with this tool =) Nice work on an interesting tool and a great new side business idea.
Joseph Donahue
Jul 06. 2021
my first information from you I must say you are awesome. I thought it would much harder but seems a little straight forward. Also I was going to add emmet to my vscode but which emmet version are you using? There are like 8 different emmets and no actual just emmet extension
Kelly Hubbard
Sep 03. 2021
Single job extensions are useless and ultimately clutter. The full screen/page capture tool. That is all it does… nothing more. I’d rather use, “”Nimbus Screenshot & Screen Video Recorder””, which not only captures a full screen/page, it can capture what we see, what we select and it can record tab or desktop into webm format. Plus it has on screen editing tools in both screenshot and video record modes. Tools to add text, shapes, various arrows, blur out text and more. Much like how news reporters on TV add arrows to live traffic reports is what the tools in video mode can do.
Jayme Silvestri
Nov 10. 2021
I truely enjoy your articles Joshua hit the ball out of the park with this list. Something for everyone.
I have these stapled to my browser:
Greenlanes sitemap tools – analysis of a sitemap page
Social Blade – youtube SEO stats
Loom – for creating quick tutorials
Love your work
Holly Hooper
Nov 10. 2021
I wanna suggest an extension that you might find useful. This extension lets you watch videos while you do other things on your laptop. It’s a resizable window so you can watch stuff while you work. The only flaw it has is that it doesn’t allow music videos to be played on their window, because they are licensed content.
Paul Brown
Dec 20. 2022
Pretty much all screen capture plugins can take screenshots of a whole page. I am using Nimbus but they can pretty much all do it. With Nimbus, you can select between capturing the whole page, only the visible part or a selected area … then you can edit it if you need (crop it, blur some parts, add arrows to point something, add texts, circle things, etc…). I really recommend it instead of the one you talked about in the .