When people say a phone was tracked, they usually mean one of two quite different things, and mixing them up is where most myths breed. The two methods are satellite positioning and cell-network location, and they behave nothing alike.
GPS, and GNSS more broadly, works by listening to satellites and computing a position on the device itself. It is precise, often within a few metres outdoors, and importantly it is private by default: the calculation happens in your phone, and nobody upstream learns the result unless your phone sends it. It is the polite method that keeps its findings to itself.
GSM triangulation works from the ground up. Your phone is always in gentle conversation with nearby cell towers, and the network knows roughly how far you are from each based on signal timing and strength. Combine a few towers and you get an estimate, sometimes a few hundred metres in a dense city, sometimes several kilometres in the countryside. It is coarse, but it works indoors and even on fairly basic phones.
The crucial difference is who holds the information. GPS results live in your hand. Cell-tower estimates live with your carrier, which is exactly why lawful location requests go to carriers, not to satellites. This is also why the movie image of a satellite pinpointing a number is doubly wrong: satellites do not send positions, and the ground-based method that could approximate you belongs to a regulated network, not a website form. Our piece on why your phone knows where you are stitches these layers together.
So when a slick tracker claims to fuse satellite lock and network triangulation from a phone number you typed in, it is blending two real technologies into one impossible smoothie. Fun to watch, physically incoherent. Live Sat Tracker leans into that smoothie on purpose, then shows you the empty blender. Peek at how the effect is built, no towers or satellites required.