Revizr free web tool which allows you collaborative document editing. It is very simple and easy to use you can simply upload your document and then invite others to edit and suggest changes.
You have the right to accept or reject suggestions. Suggestions will appear in different colours of ink then you can easily manage suggestions. No download is required for revizr. It collaborate MS Word, Open Office, HTML, rich text and plain text documents. More details you try revizr.