Why GPS Fails in Underground Parking (and What to Save)
Short answer: GPS needs a clear view of satellites, and concrete floors block it. Underground, your phone guesses, so the saved pin may be off or missing. The floor, zone and pillar number are what actually lead you back.
What happens to GPS underground
Phones fall back to Wi-Fi and cell towers, or keep the last fix from outside. Accuracy can drop from a few meters to 50 m or more, and GPS has no idea which floor you are on.
What to record instead
Floor (B1, B2...), zone letter or color, and the nearest pillar number. A photo of the pillar sign removes any doubt. Save the GPS pin too: it still gets you to the right building and entrance.
Finding the car on the way back
Use the GPS pin and a compass arrow to reach the right entrance, take the elevator to the saved floor, then follow the zone and pillar signs.
Doing it with Parkdrop
Parkdrop shows the floor, zone and pillar in big letters, signal or not, and shows GPS accuracy (±m) so you know how far to trust the arrow. One tap saves all of it.
FAQ
Why is my parking location wrong in a garage?
Satellite signals are blocked by concrete, so the phone guesses from Wi-Fi or the last fix outside. The pin can land on the street or the wrong building.
Can any app track the exact floor underground?
Not reliably. Phones cannot tell floors apart from GPS alone, which is why writing down the floor matters.
What is the best thing to record?
Floor, zone letter, pillar number and a photo of the nearest sign. Save the GPS pin too, ideally near the entrance.