I live in an area with a lot of iron. I cannot trust a compass to always point north. Generally I've had no problems in the woods: follow the trails that are on the maps, or at least stay close enough that you can always find them again and you are fine. (until of course you are not)
Phones already do that with cell towers. It's called A-GPS (augmented GPS). Cell towers, wifi, and even bluetooth, are used in addition to GPS/GLONASS/Galileo signals.
Satellites project a sphere, you need 4 in order to get to a singular point. I've outlined each step. Fourth isn't for clock correction only. And even outlined why sometimes 3 is okay, but that requires additional logic that many gps devices sometimes can't compute, and even outlined that the vast majority of devices will use way more than 4.
Oh boy, where do I even start? This comment is wrong in multiple ways. Let's break it down:
"The way triangulation works is by essentially measuring distance."
Nope. This describes trilateration, not triangulation.
Triangulation uses angles, while trilateration uses distances. GPS works via trilateration.
"1 satellite distance puts you anywhere in a radius (circle) of that satellite."
Kind of, but missing a crucial detail:
A single satellite defines a sphere around itself (not just a circle—you exist in 3D space).
"2 Satellites puts you at 1 of 2 locations where those radiuses intersect."
Wrong. Two satellite distance spheres intersect to form a circle, not just two points.
"3 satellites gives you a single location."
Mostly right, but incomplete.
In theory, three satellites narrow it down to two possible points, but one is often out in space or somewhere unrealistic, so it can often be ruled out.
However, because your device lacks an atomic clock, it typically requires four satellites to synchronize time properly.
"That's why it's called triangulation. Tri = 3"
Nope. GPS does NOT use triangulation.
The "tri" in triangulation comes from angles, not the number of satellites. GPS uses trilateration, which is based on measuring distances, not angles.
Final Verdict
This comment is a trainwreck of incorrect terms and flawed explanations. If they meant "trilateration," at least part of it would make sense, but calling it "triangulation" completely ruins their credibility.
So, in short? No, their comment is very incorrect. 🚨
Satellites broadcast a sphere, not a circle. And that sphere doesn't land on the earth as a perfect circle for relatively obvious reason... since the ground isn't perfect flat, nor is the earth perfectly spheroid.