Why a Compass App Doesn't Need Location Permission

Open a compass app, and there's a fair chance it refuses to show you anything until you grant location. That feels backwards — a compass is the one navigation tool that predates satellites by a few thousand years — and it is. Your phone finds north with a magnetometer, a chip that senses the Earth's magnetic field. It needs no GPS, no network and no permission. An app that blocks the compass behind a location prompt is either lazy or collecting data it doesn't need for the job.

Magnetic north vs true north

The magnetometer points at magnetic north. True north — the axis the planet spins on — is a few degrees away, and the difference (the declination) depends on where you are: near zero in some places, over 15° in others. To convert magnetic to true, the app needs your rough position. That is the one legitimate reason a compass app asks for location, and it should be optional: magnetic north for free, true north if you choose to allow approximate location. It also only needs a coarse position — a city-level fix is plenty for declination — so an app demanding precise location for a compass is asking for more than it needs.

When true north matters

• Reading a printed map with a marked declination, or following a bearing from a guidebook.
• Aligning a satellite dish or a solar panel to a compass bearing given in true degrees.
• Orienting a telescope.

For "which way is the sea", feng shui, prayer direction within a few degrees, or checking which way a window faces, magnetic north is fine.

Why your compass points the wrong way (and the figure-eight fix)

The magnetometer drifts, and it is easily confused by nearby metal — a laptop, a car body, a magnetic phone case, a fridge. When the sensor reports low accuracy, the fix is to move the phone through a figure-eight a few times; that sweeps the sensor through every orientation and lets the OS re-estimate its bias. A good app tells you when this is needed instead of silently showing a wrong heading. Most "the compass points east" reviews are a phone that was never calibrated, held next to a metal desk.

What the permission prompt actually means

On Android, a compass app that wants declination should request approximate location, ask only when you tap "true north", and keep working if you say no. If an app requests location at first launch, requests precise location, or shows an empty screen until you agree, the location is doing something other than declination — usually ad targeting.

Truekit's compass

Truekit shows magnetic north with no permission at all. A True N button asks for approximate location only when you tap it and uses the phone's last known position to compute declination — it never turns on GPS. It warns you when the sensor accuracy is low and needs a figure-eight, and the dial turns without ever spinning the wrong way around the 360° boundary. Free, offline, no account.

Get Truekit on Google Play — compass, level, ruler and 9 more tools.