Most people think their phone’s location comes from GPS. In reality, GPS is only one of several systems your device blends together, and understanding that blend explains both why maps sometimes think you are in the wrong city, and why airplane mode does not do what many people assume.
The satellites are only half the story
Global navigation satellite systems — GPS, Europe’s Galileo, Russia’s GLONASS, China’s BeiDou — broadcast timing signals. Your phone receives them passively; it never transmits to a satellite. From four or more signals it can triangulate position to within a few meters outdoors. Indoors or in deep urban canyons, those signals scatter and the fix degrades fast.
Where Wi-Fi and cell towers come in
To speed up a cold start, phones use assisted GPS: the network tells your device which satellites to look for based on your approximate location from nearby cell towers. Beyond that, your phone maintains a database of Wi-Fi access points it has seen, mapped against known positions. If you have ever had your location jump the moment you connected to café Wi-Fi, this is why.
The part people get wrong
Toggling off location services stops apps from reading your position, but the device still sees which cell towers and Wi-Fi networks surround it. That is enough to place you within a building or neighborhood. True radio silence means airplane mode plus Wi-Fi and Bluetooth off — and even then, the carrier still knows which tower is serving you whenever the radio is on.
Practical takeaways
If privacy matters for a given app, check whether it truly needs background location rather than while-in-use access. And if a map ever insists you are one street over, you now know why: your phone is arbitrating between satellites, towers, and wireless networks, and they occasionally disagree.
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