OnlyOffice is a productivity suite that provides tools for document management, project management, and customer relationship management. It includes a range of applications like word processing, spreadsheets, and presentations, similar to other office suites. OnlyOffice is known for its collaborative features, allowing multiple users to work on documents together in real-time. It supports popular document formats and can be integrated with various cloud storage services. A subscription typically offers enhanced collaboration tools, access to additional applications, and integration capabilities with other services.