We have moved to a new Sailfish OS Forum. Please start new discussions there.

Why does the GPS think i'm somewhere else

asked 2013-12-29 02:09:19 +0300

evvert gravatar image

updated 2014-01-08 10:47:15 +0300

eric gravatar image

I've got lousy GPS reception indoors and it's almost impossible to get a fix, that's not really a problem, i can just walk outdoors. But what buggers me is, why does the (A)GPS believe i'm almost 400km south of where I am, in a location I havn't lived in for almost 2 years? And it's spot on to that old address. If I use a browser on my computer and surf to m.here.com it shows my real (approximate) location. I've tried using the GPS when driving home, going inside, still my real location and after a while when it looses the GPS fix, it teleports me south again.

edit retag flag offensive close delete


I've noticed the almost nonexistant indoor location capabilities too and it's a problem because apps like Speedtest don't work correctly if they don't get a location fix. Android phones get an approximate location indoors in a few seconds, even the Nokia E71 (2008) is better than Jolla.

hana ( 2014-01-16 19:02:41 +0300 )edit

I think i need to debug this a little bit more so i can give a better explanation :)

evvert ( 2014-01-22 13:33:43 +0300 )edit

I am experiencing the same problem with the impossible GPS fix indoors :(

Alex ( 2014-02-25 02:09:03 +0300 )edit

2 Answers

Sort by » oldest newest most voted

answered 2014-01-16 18:16:39 +0300

chemist gravatar image

updated 2014-01-16 22:05:12 +0300

AGPS uses cell tower IDs, some providers use hybrid location services such as MAC, IPs and other network environment data - happened to have a bad 3G-tower entry and the GPS thought it is 400km elsewhere trying to get a fix swapping to 2G helped. Why do I say that? Cause it does work without hybrid location services just as good as with. OTOH without GPS you can only use CellIDs and network environment data for locating. As the here-maps does not even get a coarse location I guess it does not use such services at least not without GPS turned on. m.here.com uses network data like your IP at first if no GPS fix is available.

edit flag offensive delete publish link more


I've been surprised by the lack of assisting services, because I'd think Nokia & HERE would support them, but maybe Jolla doesn't use those services at the moment? We're obviously in the early stages of cooperation between Jolla and HERE.

hana ( 2014-01-16 19:04:56 +0300 )edit

seems more like Nokia did not implement them for Jolla yet, at least it sounded like Jolla is waiting on Nokia and Nokia might be waiting for more money^^

chemist ( 2014-02-05 01:15:53 +0300 )edit

answered 2013-12-29 04:53:46 +0300

Nux gravatar image

That's because your router was in that location and AGPS uses mainly WiFi hotspots location to figure out where you are. That's why on some mobile conferences you might end up being in New York, Japan and Amsterdam almost in the same time :-).

How does it work... Well it's a secret ;-), but your router has a MAC address and SSID which both can identify it (more or less). The router doesn't have a GPS but devices that "see" it can have a GPS active. If the device (e.g. your phone) is aware of it's location and sees your router it can report the router's position. Quite simple really. The more devices report "seeing" the router the more accurate its position becomes. The more routers your device without GPS see, the more accurate its position becomes. You can observe this in action when tracking your tablet position on e.g. Google Maps.

I'm guessing that on your computer you don't have WiFi or just your browser uses a different algorithm to track your position (probably prioritizing your IP location).

edit flag offensive delete publish link more


Before delivery of the Jolla device, that was also my assumption regarding how this should work. Unfortunately none of the AP's (6) installed in my household (Farm in mid Sweden, if you wonder why so many) has been in proximity of the other location, neither has the SSID. The only thing that actually has been in proximity is my old N9 with my nokia account logged in, which gives me the reason to believe that either, we have some kind of "intelligent" mapping between jolla accounts and nokia here data, or the N9 has somehow obfuscated the A-GPS database that Jolla uses. Could be a different algorithm on the computer since it uses wifi, or it uses different A-GPS servers.

evvert ( 2013-12-29 05:11:48 +0300 )edit

Maybe it detects not only the MAC addresses of APs but also of clients ? Well, that would be a serious oops then. :)

MartinK ( 2013-12-29 13:46:14 +0300 )edit
Login/Signup to Answer

Question tools



Asked: 2013-12-29 02:09:19 +0300

Seen: 15,367 times

Last updated: Jan 16 '14