OnlyOffice

OnlyOffice is a free software office suite developed by Ascensio System SIA, a company headquartered in Riga, Latvia. It features online document editors, a platform for document management, corporate communication, mail, and project management tools.

Key Features:

• Highly compatible with Microsoft Office formats
• Best bet for complete replacement of Microsoft Office
• Document editors, spreadsheets, and presentations
• Collaboration features for teams
• Available as desktop apps and web-based
• Self-hosting option available

Recommended for: Users who need maximum Microsoft Office compatibility while maintaining privacy.