Kopano Alternatives

Google Workspace (formerly Google Apps for Work / G Suite) is Google's encompassing selection of cloud apps for business, including customizable products under custom domain names.

The mail service which respects you.

Microsoft 365 is a subscription-based software services that licenses Microsoft Office products for on-premise or cloud-based use.

Zimbra Collaboration is an open, secure collaboration tool for email, calendaring, tasks and more. With the most innovative web application available today, Zimbra boosts the productivity of users on any desktop and dramatically reduces TCO compared to legacy platform vendors.

Nextcloud is the most deployed on-premises file share and collaboration platform. Access & collaborate across your devices. As fully on-premises solution, Nextcloud Hub provides the benefits of online collaboration without the compliance and security risks.

Kolab is entirely Free and Open Source Software (a.k.a. FOSS), and uses Open Standards. We’ll get to why this is important to us, and hope that it is important to you thereafter.

Kolab Now provides a suite of intuitive apps in a user friendly environment to make your day to day online comms easier, smarter and most importantly; secure.

OpenChange aims to provide a portable Open Source implementation of Microsoft Exchange Server and Exchange protocols.

Microsoft Exchange Server is a messaging and collaborative software product developed by Microsoft. It is part of the Microsoft Servers line of server products and is widely used by enterprises using Microsoft infrastructure solutions.

grommunio (formerly known as grammm) efficiently combines all requirements of modern, digital communication and collaboration.