Secure Data Sync.
Secure, end-to-end encrypted, and privacy respecting sync for your contacts, calendars, tasks and notes.
Easy to use and open source - it seamlessly integrates with your existing apps so you won't even notice you are using it!
CalDAV, CardDAV and WebDAV for Android.
Sync your contacts, calendars and tasks. Get live-access to your WebDAV Cloud files.
All-in-one CalDAV/CardDAV/WebDAV solution for Android.
DAVx⁵ is an open-source CalDAV/CardDAV suite and sync app for Android. You can also access your online files (WebDAV) with it.
Open source push technology.
Z-Push is an open-source application to synchronize ActiveSync compatible devices such as mobile phones, tablets and Outlook 2013 and above. With a history of over 9 years of successful synchronization with multiple backends Z-Push is the leading open source push synchronization.
Free and Open-Source CalDAV and CardDAV Server.
Radicale is a small but powerful CalDAV (calendars, to-do lists) and CardDAV (contacts) server.
The open source CardDAV, CalDAV and WebDAV server.
Open Source Groupware.
SOGo is a fully supported and trusted groupware server with a focus on scalability and open standards. SOGo is released under the GNU GPL/LGPL v2 and above.
SOGo provides a rich AJAX-based Web interface and supports multiple native clients through the use of standard protocols such as CalDAV, CardDAV and GroupDAV, as well as Microsoft ActiveSync.
This is a very experimental, not complete, not fully functionnal, probably heavily bugged project. In fact, for the moment, this is closer to a proof of concept than an actual “usable” extension. But it works as long as you don’t stress it too much :).