fruux is a unified contacts/calendaring system that works across platforms and devices.
Contacts, calendars and to-dos in the cloud.
The use of open standards such as CardDAV and CalDAV makes it easy to deploy across different devices and many different vendors. This also ensures that the user’s data does not suffer from vendor lock-in.
We're the team behind SabreDAV, the best WebDAV/CardDAV/CalDAV sync stack in the world (used by the likes of Box.com, Kolab, Atmail, Portuguese Telecom and many more):