Solaar is a Linux device manager for Logitech’s Unifying Receiver peripherals. It is able to pair/unpair devices to the receiver, and for most devices read battery status.
It comes in two flavors, command-line and GUI. Both are able to list the devices paired to a Unifying Receiver, show detailed info for each device, and also pair/unpair supported devices with the receiver.
apt-get install solaar