Viewer (Viewer):
Can view a project
Can add comments and reply to comments with the comment tool and participate in polls
Cannot edit, share, download or delete a project
Editor (Editor):
Can edit a project (including commenting and voting)
Cannot share, download or delete a project
Manager:
Can edit, download and share a project (add other users to a project)
Has additional options for Connected View, to better coordinate groups of participants
Cannot delete a project
Admin:
Can edit a project, download, share and permanently delete.
Has additional options for Connected View, to better coordinate groups of participants