GPS without 3g

[Alwinl]

Hi,
I copied the code from the GPS tutorial and am testing on a real device (Android 4.1.1) that has no sim but has internet connectivity via wifi and shows my location in Maps just fine.
GPS1.GPSEnabled is always False and hence whenever I run the test app is uses
StartActivity(GPS1.LocationSettingsIntent)
to take me to the settings screen where I have two checkboxes and both are ticked. I also checked my app under the 'apps' setting menu and it shows that access to 'my location' is allowed.
Any ideas?

 

[MotoMusher]

2 checkboxes? There should be 3 in most of the versions I have seen. Is "Use GPS Satellites" checked? I have that, Use Wireless networks, and location and google search. "GPS" also has to be "on" by pulling down the notification bar from the top.

 

[Alwinl]

Under 'Settings', 'Personal', 'Location Services' (same screen as StartActivity(GPS1.LocationSettingsIntent)) I have only 2 settings:
-Google location service - location determined by wifi
-Location& Google search - let google use your location to improve search results and other services

I am not sure what you mean by 'pull down notification bar', I don't seem to have anything like that in settings or when in my app. When the app starts it does say that it will have access to my location.

The GPS must be working because it shows my position on Maps.

 

[MotoMusher]

Maps could be inferring your position from a cell tower, they don't need gps. Are you sure you phone has a GPS?

As for pull down. Put your finger on the clock at the very top of your phone and drag down to the bottom. This should pull down a "window shade" of sorts. You should be able to turn wifi on and off, change screen brightness, bluetooth etc. There should be a gps option in there.

What phone do you have?

 

[Alwinl]

After some research it seems my device does not have GPS or cell capabilities so at least that explains why the GPS library is not working - I just assumed it had GPS because it was able to detect my location.

The thing that confuses me is how the device knows my location to within 10m accuracy using only wifi - although not related to this thread I would be very interested if anyone has info on this.

 

[boredsilly]

I believe google uses your wifi router to get your position. They came around in those vans recording wifi's and their gps locations. You can get your gps coordinate using the ABWifi library I think.

 

[rbsoft]

Have a look at this thread:
http://www.b4x.com/android/forum/threads/cell-location.8614/#post-63727

and here:
http://www.theguardian.com/technology/2011/apr/22/iphone-android-location-based-services

 

[Alwinl]

Interesting - I am in a suburban environment where although I assume there will be a few wifi networks, mine is the only one my devices detect (due to range issues probably). I can see how location can be determined from cell towers but to know my location (pretty accurately) purely from some arb wifi network name just seems a stretch.
I must do some tests with this device in other locations and see what the results say.

 

[rbsoft]

I had made some tests a while ago using the Wifi Library. GPS was off. Driving through some rural area I had a fairly vague position (precision: 2 to 5 km) from cell towers. As soon I got to areas covered by building the positioning was very exact.

Apple, Google, Microsoft, and others have almost every wifi rooter, its mac adress, and its location in their database. That's why they can provide location based services even to devices that have no gps. Here is a good article about it:
http://www.zdnet.com/blog/networking/how-google-and-everyone-else-gets-wi-fi-location-data/1664

 

[Alwinl]

I really didn't know this data collection was going on, amazing. I don't mean to harp on the topic but let's say the big brother's had my router's mac logged against a few gps co-ords that were sent back from other devices (gps/cell enabled) that had connected to my network, these co-ords could be anywhere in a 50m+ radius so there must be some pretty clever algorithms to work out the 'central' point with such accuracy

 

[siddsg]

Hello,
I want to be able to detect if the 'Use wireless networks' option is enabled or not, so that the user can enable if required.
Would you know how to do that?
Thanks,
Siddharth