The UI allows us to add multiple devices to our Person. Not knowing the ins and out, I had setup my phone entity (from the HA Android app), as well as the network entity from the Unify integration. Either should be able to tell if I am home or not, but the phone app obviously does a better job since it has the ability to provide GPS coordinates (if enabled) to show where I am when not home.
However regardless of which order I put the devices in the list, HA always uses the network tracker as primary. Instead of the phone app entity which provides more detailed info. I found out (eventually) that by removing all my other devices and just having the phone app there, my person.name entity actually inherited GPS attributes and allowed me to do more with Zones.
So why do you allow multiple devices attached to a person? Because that definitely sets beginners (as it did me) up for failure.
And if there is a reason, how can we “prefer” a certain device as the main one? Since it currently seems to pick my network one with just a home/away status, and my person.name entity then lacks GPS coordinates.