Wrong street, wrong city, or a blue dot that jumps
A phone works out where it is in three quite different ways, and the failures look the same from the outside. A blue dot in the wrong city is almost never a broken GPS receiver; it is the network-based method giving a confident wrong answer. A dot that drifts and jumps between buildings is the opposite problem. Telling them apart takes about two minutes and decides which of the fixes below is the right one.
The three ways a phone locates itself
| Method | Typical accuracy | When it goes wrong |
|---|---|---|
| Satellites | A few metres outdoors | Indoors, in a tunnel, between tall buildings |
| Nearby WiFi networks | Tens of metres, instantly | When a router has moved house since it was catalogued |
| Mobile towers | Hundreds of metres to kilometres | Rural areas, and at the edge of coverage |
| Sensor fusion and dead reckoning | Fills short gaps | Drifts if the compass or step count is off |
| IP address, in a browser | City at best, often wrong | Any VPN, any corporate network |
Advertisement
Working out which problem you have
- Go outside, with a view of the sky, and wait a minute A first satellite fix from cold can take thirty seconds or more. If the dot becomes accurate outdoors, the receiver is fine and the problem is indoor positioning.
- Check a diagnostic app for satellites in view One of the GPS test apps below shows how many satellites are seen and how many are used. Plenty seen and none used means an obstructed view; none seen at all points at a setting or a fault.
- Look at whether location accuracy is switched on Android's setting, variously called Google Location Accuracy or improve accuracy, is what lets WiFi and mobile networks help. Off, the phone is satellite-only and slow indoors; on, it is fast and occasionally confidently wrong.
- Check WiFi scanning is allowed Location uses nearby network names without connecting to them. If WiFi is off entirely, indoor accuracy collapses, which surprises people who turned it off to save battery.
- Rule out a mock location app In developer options there is a select mock location app entry. Anything set there overrides your real position, and a test or game utility installed and forgotten is a classic cause of a permanently wrong city.
- Check battery saving for the app that is wrong Aggressive power management delays location updates, which shows up as a dot that lags a street behind you rather than one in the wrong place.
- Remember that a VPN does not move the phone It changes what websites think, because they use your address on the internet. The maps app still uses satellites, which is why the two can disagree completely, and that is not a fault.
The apps worth having for this
The simplest satellite view: how many are visible, how many are used, the signal from each and the accuracy figure. The first app to install when location is misbehaving.
More detail, including a sky view and sensor readings, and the long-standing tool for this job. Some of its assistance-data features do nothing on modern Android, which is worth knowing before reading too much into them.
A clean readout of position, speed, accuracy and satellites, with logging. Good for checking whether accuracy improves when you move somewhere with a clear view.
A larger toolkit with a dashboard, waypoints and a compass, useful once you have established there is nothing wrong and you want to use the data.
Reads every sensor the phone has, which is how you confirm the magnetometer is the thing misbehaving rather than the positioning.
The same idea with a clearer presentation, including a live compass reading you can hold next to a known direction.
A plain compass with an altimeter, for testing heading separately from position. If this is wrong, calibrate rather than reinstalling maps.
Shows which mobile cell you are attached to and its signal. When location falls back to towers, this is what it is falling back to, and a weak reading explains a lot.
Coverage and speed testing, useful for establishing that the area genuinely has poor mobile data rather than the phone having a problem.
Offline maps with a raw GPS readout available, so you can see position without any network assistance at all. The cleanest way to test satellites alone.
The friendlier offline map for the same test, and a sensible thing to have on the phone regardless.
Uses the phone's own sensors with no network: position, bearing, altitude and a backtrack trail. A good sanity check on what the hardware can do unaided.
Device details including the sensor and hardware list, which settles the question of what positioning hardware the phone actually has.
Included for one feature: its calibration prompt and the accuracy circle, which is the fastest visual indication of whether the phone is confident or guessing.
The fixes, in the order worth trying
- Going outside and waiting for a proper fix
- Turning location accuracy and WiFi scanning on
- Clearing a mock location app
- Exempting the affected app from battery optimisation
- Restarting the phone once, properly
- Installing a GPS booster or fixer app
- Clearing the maps app's data repeatedly
- Factory resetting for this alone
- Blaming a case, for satellites
- Expecting a VPN to change the blue dot
A word about the apps that advertise themselves as fixing or boosting GPS: there is nothing for them to fix. Position comes from a receiver and from Google's network database, and no third-party app has privileged access to either. The ones that ask for permissions and show advertisements are the entire product.
If satellites are visible and used, accuracy outdoors is a few metres, and the dot is still in the wrong place inside one particular app, the problem is that app's permissions rather than the phone. Check whether it has been granted approximate rather than precise location, which is a setting people turn on deliberately and then forget.
Go outside and check the satellites first. Then location accuracy, WiFi scanning and mock location, in that order, and ignore anything advertising itself as a GPS fixer.
Frequently asked questions
Why does my phone show the wrong city entirely?
Almost always network-based positioning using a WiFi network whose catalogued position is out of date, typically a router that moved house. Going outside for a satellite fix corrects it, and so does turning WiFi scanning off temporarily.
Does GPS work without a data connection?
Yes. Satellite positioning is entirely separate from the mobile network. A connection only makes the first fix faster and supplies the map, which is why offline maps and no signal work perfectly well together.
Is a GPS repair app worth installing?
No. There is nothing for such an app to repair, and most of them exist for the advertising. Use a diagnostic app to see what is happening and change the system settings.
Why is my location fine in one app and wrong in another?
Permissions. An app granted approximate location gets a deliberately coarse position, and an app restricted in the background gets a stale one. Both are settings on the app rather than faults on the phone.
Read next
Nothing has infected your phone. Something you installed has permission, and the fix is a list in settings.
A phone will happily run a keyboard, a mouse and a memory stick. It will not power a desktop hard drive.
Hard and fast are different things. Almost every game confuses them, and these do not.
