“How/Why does the GPS in your smartphone rely on where the model says magnetic north is? Hopefully they are keeping good track of where the dragons be.”
They work off satellites in orbit. They give you information that is translated into current geomagnetic positions. Actually it would be better if they made it true north positions but this is trivial. Your GPS will work just fine.
Our reliance on geomagnetic positions is really an anachronism dating back to the sailing days that totally relied on magnetic north. GPS satellites will tell you exactly where you are with precision. I have a gps in my glider that I down loaded for free on my tablet. It tells me where to go based on the current geomagnetic north. It would be easy to change all of this based on polar north. As said, it is an anachronism that will be gone in the future. However, I will not throw my magnetic compass away!
Had a tour of duty at a LORAN-C radio navigation transmitter that had been upgraded for FAA-IFR. 100mHz radio waves or digital signals from a satellite relies not on magnetism and the only time the end user was affected by crazy magnetism was during sunspot activity. These guys are acting like Magellan is about to set sail over the north pole in his wooden ship with a Cracker Jack compass, a sextant and no map.
There is only one problem with GPS. GPS does not resolve 'north' if you are not moving, but your compass does.
https://gis.stackexchange.com/questions/183862/how-does-a-gps-device-determine-bearing