Chrome: When you collaborate on a project, you may need to have documents approved by other team members. Workflows is an add-on for Google Docs that brings this feature to Google's online office suite.
Google Docs has a commenting feature that is very helpful when editing documents, but Workflows takes things a step further. Install the add-on and access it from the Add-ons > Workflows menu in Docs. You can use the add-ons to get simple approvals for new documents -- whoever you invite to the workflow is able to approve or reject as they see fit.
You can also use Workflows to gauge opinion. Invite several people to approve a document and you can see what the general consensus is. Reviewers can add comments as well as accepting or rejecting a document, so it's a good way to collaborate when members of a team are not able to speak to each other directly.
Workflows is a free and effective way to get a document digitally signed off by a number of people on the team without the need for specialist software.