You can have access to your IP Address via the menu Information → Network Information.
Lakka use Avahi, so you should be able to use the hostname lakka.local in place of the IP when trying to connect Lakka on your local network. If it doesn’t work, use the real IP.
ping lakka.local
If you’re on Linux, you can install the arp-scan utility, and run this command in a terminal:
sudo arp-scan -l
You will get this kind of output
Interface: wlan0, datalink type: EN10MB (Ethernet)
Starting arp-scan 1.9 with 256 hosts (http://www.nta-monitor.com/tools/arp-scan/)
192.168.0.14 f4:ca:e5:67:fe:7e FREEBOX SA
192.168.0.1 cc:3a:61:37:e2:95 SAMSUNG ELECTRO MECHANICS CO., LTD.
192.168.0.1 cc:3a:61:37:e2:95 SAMSUNG ELECTRO MECHANICS CO., LTD. (DUP: 2)
192.168.0.5 d0:92:9e:a7:6b:24 (Unknown)
192.168.0.254 f4:ca:e5:49:f6:b5 FREEBOX SA
5 packets received by filter, 0 packets dropped by kernel
Ending arp-scan 1.9: 256 hosts scanned in 2.673 seconds (95.77 hosts/sec). 5 responded
If you’re on Windows, you can install this tool: LAN Scanner. Select “SSH” (port 22) as the service to be searched for, and hit Scan. One of the active IP addresses listed should be your Lakka box.
ifconfig | grep broadcast
arp -a