Google Drive is Google's file sync app that lets you store all of your files online alongside your Google Docs documents, and keep them synced with all of your devices.
Your brand reviewer gets the current campaign draft and the decision needed together on the review task.
Your quote approver can review the latest client scope beside the proposed terms, with differences called out before they decide.
Your reviewers see the brief beside the asset, with the brand decision they need to make clearly stated.