DAVx⁵
Grommunio is an open source Exchange alternative, based on Vienna (Austria), which provides Email, calendar, contacts, chat, video and files on one platform.
DAVx⁵ settings
Base URL: https://grommunio-demo.com (for the demo) - or your self-hosted instance's URL
Contact group method: groups are separate VCards (or the method used by your other clients)
Current Limitations (2026/09/30):
- Profile picture is not stored.
- Creating a collection from within DAVx⁵ only accepts one type: either calendar or tasks
- Journals not supported
- Collection colors are discarded after creation