Version 9.3.43 is available upstream. Please consider updating! It seems that version 9.3.43 is available upstream, while the latest version in the Gentoo tree is 9.1.120. You think this warning is false? Read more about it here.
UniFi is a management controller software for Ubiquiti UniFi APs.
Its purpose is to configure and monitor all those APs.
Also all kind of statistics are collected, which can be accessed through UniFi.
There is also an internal RADIUS server, which can be used for WPA2-Enterprise.