What is the IP address of my iphone when my computer is connected to the internet using that iphone's personal hotspot?

I have this program on my mac that streams my gps location over the private network.

When on the road, my program needs an internet connection as well as the gps data, so I need to pair to my iphone to get internet. After doing this, however, my program can't determine my iphone's IP address so I can't get the location data.

Does my iphone have an IP address when it's the "router" effectively, via personal hotspot??