And, sadly, I'm not techy enough to explain. In fact, it's darn near miraculous that I stumbled across it figured it out myself. :o
Here's a try: Our phones (well, all modern cell phones) have GPS location stuff in them. The life 360 service tracks the phones of people in your "family circle." There's a web site, too, I've found, and I am able to see where DH is on his trip to California. I just have to hit "update" occasionally and it shows me where he is on a map.