XO is a web interface to visualize and administrate your XenServer (or XAPI enabled) hosts.
It aims to be easy to use on any device supporting modern web technologies (HTML 5, CSS 3, JavaScript) such as your desktop computer or your smartphone.
XO is developped by Vates SAS a small French company and released under the AGPL v3 licence. a XO is currently under development and may be subject to important bugs.
Would you like to know more?
Xen Orchestra has three bugtrackers: one for the server, one for the interface and the last one for common issues or when you don't know to which part it is related to.