There is no additional configuration need to scan vlans or subnets. Lansweeper will be able to scan all devices in the network which meet the scanning requirements. Regardless of which vlan or subnet they are on.
For phones specifically, when a mobile phone is connected to your network, Lansweeper will retrieve the MAC address from its own ARP table. In cases where your phones are in other subnets, Lansweeper will not be able to retrieve the MAC address for these phones.
