Unity Collaborate is part of Unity Teams. Unity Teams enables small teams to save, share, and sync a Unity Project in a cloud-hosted environment. Using Collaborate allows your entire team to contribute to a Project, regardless of location or role. For more information on Unity Teams, see the Teams page on the Unity3d website.
Collaborate allows you to publish your projects to the cloud for storage. Collaborate maintains a history of the versions of the Project that publish, allowing you to restore individual files or your entire Project to an earlier state.
You can add team members to your Projects; allowing you and team members to work together. Collaborate continuously monitors changes that are made by each team member and displays a badge on the files that they have changed, but not published yet.
You can view the changes. You can then choose to revert the changes on your file or publish them and handle any merge conflicts that might occur.
Collaborate is designed to support multi-disciplinary teams (that is, teams with a diverse mix of developers, artists, audio experts and other specialists) that work together on projects. Collaborate is in full release starting with Unity 2017.1. Collaborate is in beta for versions of Unity prior to 2017.1.
To enable Collaborate, open the Services window in the Unity Editor (menu: Window > Services). To launch Collaborate while you’re working, click the Collab button in the Unity Editor.