Alternativ till Horde för Software as a Service (SaaS) med öppen källkodslicens

• Software as a Service (SaaS)
  Alla plattformar Windows Mac Linux Chrome OS Android iPhone Android Wear iPad Android Tablet Web Self-Hosted Software as a Service (SaaS) PHP JavaScript BSD Android TV Chrome Docker MetaMask Thunderbird Cloudron OpenPGP Kubernetes OpenShift
• Open Source-licens
  Eventuell licens Gratis licens Open Source-licens Kommersiell licens