[nashashmi]

I believe it is the public IP address and not the local IP address that brings everyone to the same page.

[jonalmeida]

I don't think that's true. I'm connected to a VPN using the built-in VPN client but none of my traffic is going through it (i.e. Send all traffic over VPN connection is unchecked) and my public IP is still the one that my phone has.

EDIT: It seems that the displayed IP is only incorrect, but the service still works over your local IP.