GAT+ by GAT Labs is a third-party application developed for Google Workspace that provides Super Admins with powerful auditing and reporting capabilities for their domain. It serves as an alternative to the 'Reports' feature in the Admin console and is included in all pricing plans. GAT+ is necessary for using other GAT products and requires access to API permissions for each Google Workspace app. GAT+ offers domain-wide auditing of files, emails, and more using configurable filters.