Why does FusedLocationProviderApi never report accuracy better than 10m? Is this documented?

Question

A data collection app that used LocationManager directly was updated to use FusedLocationProviderApi. With LocationManager, most devices quickly report 5m accuracy or better when collecting location. With FusedLocationProviderApi, the best accuracy ever reported is 10m.

I have just installed a location demo app and see the same behavior (https://github.com/will-quast/android-location-demo). In the Fused Location activity, if I only show GPS location, the accuracy changes as I get a better view of the sky and it can go down to 2m. If I only show fused, I get the same point as reported by LocationManager. This makes sense -- I have Android set to use GPS only for location and priority is set to PRIORITY_HIGH_ACCURACY so I expect the two points to always be the same. But the best accuracy ever displayed is 10m with the fused provider.

Why does the fused provider never report an accuracy less than 10m? Is this documented somewhere? Is there any way around it or should LocationManager always be used when a sense of accuracy is needed?

FusedLocationProviderClient is not currently an option because it requires an update to Google Play and this app is used in resource-constrained areas where a Google Play update is prohibitively large. It would still be useful to know whether it does report sub-10m accuracies. It also never reports an accuracy below 10m with Android settings set to use GPS only.

Edit 4/9 - Related questions:

• Dramatic shift in location accuracy distribution starting February 15
• Wierd and very unexpected issue with location.getAccuracy()
• FusedLocationApi Performance Issue: Accuracy seems capped at 10.0 meters
• Cordova geolocation accuracy gets capped at 10 meters

Kimono

can you add some code if you don't mind? – Medulla

@G.Dator See github.com/will-quast/android-location-demo/blob/master/… and github.com/opendatakit/collect/blob/… – Bouillabaisse

@Hélène Martin: What accuracy you are getting? – Hexapody

@jiteshmohite With FusedLocationProviderAPI I get an accuracy of 10m. With LocationManager I get an accuracy of 2m. – Bouillabaisse

Would love some insight into why this question was down voted so I can write better questions in the future! – Bouillabaisse

@HélèneMartin the issue has been reported here issuetracker.google.com/issues/79189573 – Whereabouts

I answered a similar question here #49348989 – Whereabouts

Good to know we weren't all going crazy! Doesn't feel like a great idea to trust FusedLocationProvider anymore, though. – Bouillabaisse

Answer 1

This was confirmed as a Google Play Services bug on the Google issue tracker. A fix that allows accuracies down to 3m is projected for Play Services 13.4.0. It's unclear why it will be capped at 3m rather than using the accuracy reported by the raw location source.

Kimono

Answer 2

No. It is best effort only. No guarantee.

If you have a good devices, and in a location which has large number of Android user. (which for example, SSID database will become more accurate), it can go to 2-3m accuracy.

Otherwise, mixing location information from different source will have a larger variance, and result as lower accuracy.

e.g. Source A accuracy is 5m. Source B accuracy is 15m.

Using Source A alone of course accuracy is 5m. But if mixed A and B, the accuracy of course will be >= 5m. (consider adding noise to clean data)

Ivanovo

Thank you, that does make some sense though it is surprising that given a high-accuracy source it still mixes, especially when Android settings say to use GPS only. The 10m limit seems like a hard one when the device is set to use GPS only. Do you know why? I can't find the source for FusedLocationProviderApi, is it available? – Bouillabaisse

Even if A and B with same accuracy, what if A and B are telling you different result? It will be giving you a lower accuracy answer. (larger radius centered in the avg of A and B may be) Have you try turning off wifi and remove sim card? Google Play Services is not open source. – Ivanovo

You're absolutely right that if two sources are available the behavior makes sense. If Android settings are set to GPS only, I would expect it to use the sole source, though! Turning off wifi and leaving out the SIM card results in the same behavior (hard stop at 10m accuracy). I didn't realize Play Services wasn't open source, thank you. – Bouillabaisse

We are experiencing the same issue, see #49348989 – Whereabouts