Database Users

Assisted GPS - Don't use it!

My Touch Pro ran TomTom flawlessly until a couple of months ago when I got a problem with the GPS device (not the signal) being lost every few seconds. It would reappear again for about 5 secs then off again. Despite soft resets etc, I suspected it might be the SD card at first as I tried many restart combinations with the card in/out etc and as it seemed to help on one occasion I put it down to that. But it did happen on a regular basis.
I now have the X1 with its superb GPS implementation, I was very impressed for a few days... until you guessed it, this problem started happening again!
Luckily I remembered the only setting I had done prior to this occuring was to use the Advanced Config application, where I enabled the AGPS feature. So... I went back in and disabled it and the problem disappeared immediately. I used Advanced Config on the Touch too, so that must have been the problem for sure.
I notice that AGPS is disabled by default. Why HTC did this must mean there is a problem with this feature.
So be advised, not to use the AGPS unless anyone knows good reason to and has a fix for the problem I mentioned.

I ran into the same problem. Turned on agps in advance config, used tomtom 7 and keep getting drop signal. It would pick up the sat signal for a few second and lose it, what interesting though when I use google map it would track me fine, no lost of signal. I can see my "dot" on google map moving along. When I drive, haven't tried it with other nav software to see if this was an issue. I still wonder why they have agps turned off though as default.

i think even if its set to "disabled", its enabled. a-gps must be hard coded in the hardware itself!
ps: i have the same problems when its "enabled".

I think it's the AGPS file that might have corrupted. You can solve this by re-download AGPS file and everything will be fine.
It happened to me once or twice, but it's not a reocurring problem so I did not bother much.

which agps file?

Guess you talk about an A-GPS setting in Tom Tom?
I cannot follow your conversation. With Mobile Navigator, which has no switch to enable or disable A-GPS it works pretty fine.
Sat-fix within seconds - thanks to the provided A-GPS function of the X1, which I don't think can be disabled on teh X1, until you don't update the information frequently with the Quick-GPS application.
Maybe Tom Tom can't interpret the A-GPS information?
How long does a Sat-Fix in Tom Tom take, when you disable A-GPS (in Tom Tom)?
Eric

we are talking about a tool called "advanced config tool". there is an option of enabling and disabling a-gps. "disabled" works best for most users...
you can have a 3d fix in seconds also with no a-gps.

Eric X1 said:
I cannot follow your conversation. With Mobile Navigator, which has no switch to enable or disable A-GPS it works pretty fine.
Sat-fix within seconds - thanks to the provided A-GPS function of the X1, which I don't think can be disabled on teh X1, until you don't update the information frequently with the Quick-GPS application.
Maybe Tom Tom can't interpret the A-GPS information?
How long does a Sat-Fix in Tom Tom take, when you disable A-GPS (in Tom Tom)?
Eric
Click to expand...
Click to collapse
It's incredibly quick (even indoors) to fix a position without AGPS. I admit I haven't knowingly had any noticable problems outside of TomTom but this is something I use a lot. It copes admirably inside, in built-up or shaded areas. No real need for AGPS then! I did try updating my QuickGPS file by the way, to no avail. Disabling was the only fix!

The FIX IS TOO FAST!!!
But I don't have this problem.......

DocMAX said:
we are talking about a tool called "advanced config tool". there is an option of enabling and disabling a-gps. "disabled" works best for most users...
you can have a 3d fix in seconds also with no a-gps.
Click to expand...
Click to collapse
My X1i doesnt have an "adavanced configuration tool" application. Is this a 3rd party addon that you have installed, or is my device just configured differently?

DocMAX said:
which agps file?
Click to expand...
Click to collapse
xtra.bin in \Windows directory I believe
one way to verify if the problem is due to the AGPS corrupted file, is if you encounter the problem, delete the xtra.bin and see if the problem goes away.

kiwiandy said:
My X1i doesnt have an "adavanced configuration tool" application. Is this a 3rd party addon that you have installed, or is my device just configured differently?
Click to expand...
Click to collapse
you have to download it http://forum.xda-developers.com/showthread.php?t=317070
it's our swiss army knife, but be careful

I think people may be getting confused between a-gps and what quickgps does.
My take on this is:
QuickGps downloads a file which contains a list of satellites to speed up getting a signal. Works very well on the x1
this is governed by HKLM/Software/HTC/QuickGPS
A-gps gets an approximate location from your cell tower and feeds 6 virtual satellites signals through the com port set up in the control panel.
It constantly does this, using memory-map software you can see that the signal drops and comes back every second or so. it seems to overwrite what is actually coming from the gps chip as I've seen 4 high quality satellite signals disappear to be replaced with 6 from the a-gps nowhere near where I was.
There's a setting in the registry section concerning A-gps which has "GPSmode" which is set to 2 I wonder what the other values are and do, I havent played with those yet.
You can change the refresh interval I set mine to be 5 when on foot
HKLM/Software/HTC/SUPL_AGPS

I agree with pretty much what you have said (the difference between Quick GPS [sometimes also known as Assisted/A-GPS] and the conventional, location-based AGPS)
However, I don't believe, unless somebody scientifically, or empirically prove, that the phone will receive virtual satellite feed/signal once it acquire the proximity based on the LBS signal. Because to do that, you need to have a data carrier, and it's either via GPRS/UMTS data connectivity (not possible since I would have noticed the data transmission), or radio frequency that satellites transmit on. It can't be GSM/W-CDMA since they operate on the different frequency as GPS, or if it indeed transmit the "virtual satellite signal" on the GSM/W-CDMA network, then I'm sure you will notice it as part of your monthly telco billing?
You may argue that the server is transmitting the virtual satellite signal on the GPS radio frequency, if so, that'll be new development in the AGPS technology since HP iPAQ 6515 first come out employ. However, there are few consideration point;
1. GPS radio frequency does not operate well across barriers, which means the 'virtual satellite transmitter' must be transmitting at a higher ground otherwise it won't work
2. The GPS receiver must be able to reconcile signal from virtual satellite signal and 'real' satellite signal, which means added layer of processing at the phone end, which in my opinions offer more complexity than effective solution.
That said, I just read that the Quick GPS service provider supports 50bit navigation raw data streaming, so I might be wrong afterall.
fards said:
I think people may be getting confused between a-gps and what quickgps does.
My take on this is:
QuickGps downloads a file which contains a list of satellites to speed up getting a signal. Works very well on the x1
this is governed by HKLM/Software/HTC/QuickGPS
A-gps gets an approximate location from your cell tower and feeds 6 virtual satellites signals through the com port set up in the control panel.
It constantly does this, using memory-map software you can see that the signal drops and comes back every second or so. it seems to overwrite what is actually coming from the gps chip as I've seen 4 high quality satellite signals disappear to be replaced with 6 from the a-gps nowhere near where I was.
There's a setting in the registry section concerning A-gps which has "GPSmode" which is set to 2 I wonder what the other values are and do, I havent played with those yet.
You can change the refresh interval I set mine to be 5 when on foot
HKLM/Software/HTC/SUPL_AGPS
Click to expand...
Click to collapse

zenkinz said:
I agree with pretty much what you have said (the difference between Quick GPS [sometimes also known as Assisted/A-GPS] and the conventional, location-based AGPS)
However, I don't believe, unless somebody scientifically, or empirically prove, that the phone will receive virtual satellite feed/signal once it acquire the proximity based on the LBS signal. Because to do that, you need to have a data carrier, and it's either via GPRS/UMTS data connectivity (not possible since I would have noticed the data transmission)
Click to expand...
Click to collapse
when you enable a-gps in the registry it establishes a data connection, or at least it does on my phone.
In my house I get a variable signal, it can drop the data connection easily (and does)!
When I first tried A-gps enabled in the registry it tried to connect, couldnt and memory-map reported no signal. It then connected I got 6 satellites listed till the data connection dropped. This makes me think it's using a data connection.
I disabled all data connections using paul modacos "nodata" and didn't get any "satellites" picked up. My quickgps was upto date at the time and outside I would expect to get a decent "proper" satellite lock.
the SUPL-AGPS section of the registry also contains the following.
Server IP 10.1.101.63
Server Port 7275
Which suggests some form of data connection. Remember this has nothing to do with quickgps or the ephemeris data that gets.
Have a look at http://wmexperts.com/articles/gps_vs_agps_a_quick_tutorial.html
&
http://en.wikipedia.org/wiki/GPS_Phone
A typical A-GPS-enabled cell phone will use a data connection (internet, or other) to contact the assistance server.
Click to expand...
Click to collapse
-----------------------
edit Have just tried again to confirm what I wrote and not getting anything through a-gps at all! I wonder if there's something in this custom rom that's changed things.
But I am being told Ive got a HDop of 666.6m which is a bit spooky..
step outside and I got 9 satellites with 8m hdop back inside and I'm getting standard fix 5 sats 2m HDop flashing on and off every second (signal/no signal) but no data connection being used, so it looks like I'm wrong, so I'll take it all back!
Need to work out what's going on now..

I was having this same issue. At least its good that its not just my device. I tried deleting xtra.bin from both \windows and \temp and it did not help.
Just some clarification on QuickGPS and AGPS. For a regular stand alone GPS to connect, when it first finds a satellite it must download ephemeris data. The ephemeris data contains info about where all the GPS sats currently are in the sky. The ephemeris data is broadcasted by every satellite periodically. A regular GPS must wait for the beginning of the next transmission. If signal is lost mid transmission, the GPS reciever must wait for the next transmission and start all over again. Only once this data is downloaded can a lock begin to be calculated. What quickGPS does is download the ephemeris data from the internet so that next time you request a gps lock, this sometimes lengthy process can be skipped. quickGPS downloads a file called packed ephemeris and places it I believe in the windows directory.
AGPS on the other hand simply supplements info from the sattellites with info from the cell network. What towers you are currently near gives an approximate location (the mechanism that google my location uses) which then tells you which satellites to look for. When fards said it feeds virtual satellite info, he doesn't mean it actually broadcasts fake satellites via RF. It just feeds extra info to the GPS driver. Also, there are lots of calculations to do to maintain a lock. Once the receiver is getting sattelite signals it can send this information over the internet to the AGPS server which is a much more powerful computer that can do these calculations much faster. The server calculates the lock for you then sends you your position information back over the internet. This is why apgs enables a data connection.

HTC Snap, GPS not detecting satellites

I can't get a satellite lock on my HTC Snap.
I have enable "use GPS" in google maps. google maps will search for satellites and after sometime come back saying weak signal & some recomendations to look for clear view of the sky.
Garmin XT also can't search GPS satellites. I install GPS Test, it seems that there's a GPS hardware but somehow the signal reception is super weak.
I have sent my Snaps to HTC service center and the best thing they can do is change the mainboard. This also show no result.
Anybody, please help. i'm starting to get frustrated with this GPS issue...

Bing GPS
I use the Bing app and have similar issues establishing GPS signal. This is my first GPS device so I'm not sure if this is normal, or if the phone is crap for GPS, or if I'm doing it wrong. I try to keep the QuickGPS updated, but that doesn't seem to help. I thought AGPS was supposed to be fast, but faster compared to what? Maybe this is 'fast' for GPS. I have seen friend's full on GPS devices and they seem to pickup pretty quick. So... who knows?

One thing to definitely try is make sure quickgps is up to date and automatically downloading. garmin could NOT find my location without that up to date and it would show one red bar signal strength. once i loaded up quickgps, updated it, and ran garmin again, full green signal.

It's The GPS Hardware ...
I've tried it all with my Dash 3G -- and concluded that it's the GPS in the phone that is garbage. I've since switched back to my trusty OnCourse Bluetooth GPS and I get a lock in Google Maps in less than 30 seconds and in Garmin XT in less than 10. IMHO, the GPS is certainly a weakness on this phone.
It finally sunk in for me when I lost signal 9 times while walking a few miles down Beacon Street in Boston. Holding the phone in my hand it kept dropping the signal over and over again. So I gave up. Built in GPS is handy in a pinch (when you have 30 minutes to wait for it to find a signal) but for serious navigating I use my Bluetooth GPS exclusively now.

No true at all. the gps in the Ozone is amazingly fast.

drewcam888 said:
No true at all. the gps in the Ozone is amazingly fast.
Click to expand...
Click to collapse
I completely agree. Simply because something is not working like it should for these others does not mean that the GPS is not good. I use garmin xt with my ozone and its is extremely fast at updating my position as i'm driving along.

Problem solved
Let say that i'm in a really bad luck. this is my first GPS device and its not working. After the 2nd time come out from the service center (2nd concecutive mainboard), then the GPS is functioning, normaly....
my maple can get lock on GPS signal quite fast. with AGPS updated, it can get signal lock within seconds (given you have a clear sky view). i found that it could takes some time for Garmin XT to get GPS signal, so I use GPS Test to speed up the process then start the Garmin XT.
so for those who can't get GPS signal. it's definitely your hardware. I also found that the online customer service officer at HTC is just a mere lips service / useless. they keep telling me to be patient and patient without real action.

There's a free GPS testing tool for Windows Mobile called GPS Test. Once that set up, you can find out which serial port is used by the GPS receiver in your Windows Mobile, and set Google Maps GPS setting accordingly. Once it's set up, Google Maps can easily find multiple satellites if you're on open space. Once it's using GPS, your location on Google Maps will be a pin point, rather than a large circle denoting your approximate location.
PS: Found out with GPS Test that my GPS receiver in my Snap is using COM4 port at 9600 bps
Sincerely,
Paul Pambudi

WIND Mobile HTC Maple users not getting GPS working PLEASE READ!
I went through four HTC Maples (two accounts each 1st phone was a warranty exchange for another non-related problem). Each of the four Maples could not lock in single GPS satellite. WIND tech support had no clue after many calls and tests run at their tech support offices in Toronto. WIND recommended that I get in contact with HTC directly to see if they might have a solution.
One call to HTC started the ball rolling and setup a trouble ticket. Within 3 days and about seven call backs to trouble shoot, HTC had the solution and both of our Maples now have fully functioning GPS with Google Maps.
The problem was in the ROMs that had an old version of Google Maps (both their WM 6.1 and WM 6.5 HTC Maple ROM for WIND accounts).
Solution: using the Maple's browser go to m.google.com/maps and install the latest version. Problem solved!
HTC customer service in North America ROCKS!!!!!!!!!!
Will I buy another HTC product? HELL YA!!!

Here's a gem!
My Snap used to take 30-40 seconds on a cold start to get a location lock (with aGPS turned on).
I installed the attached CAB (which just adds some registry keys, also found here: Here), which makes the phone use Google's aGPS server, and got a cold start GPS lock in 7 seconds... indoors!

arpitp said:
Here's a gem!
My Snap used to take 30-40 seconds on a cold start to get a location lock (with aGPS turned on).
I installed the attached CAB (which just adds some registry keys, also found here: showthread.php?t=544421), which makes the phone use Google's aGPS server, and got a cold start GPS lock in 7 seconds... indoors!
Click to expand...
Click to collapse
The thread you listed for registry key changes doesn't appear to work.
Any chance you might be able to list it again?
Thanks.
AE!

AquiEsta! said:
The thread you listed for registry key changes doesn't appear to work.
Any chance you might be able to list it again?
Thanks.
AE!
Click to expand...
Click to collapse
Sorry, the link was bad. I'm used to posting links in that format from another forum. Anyhow, it's fixed in the last post, and here it is as well:
http://forum.xda-developers.com/showthread.php?t=544421

arpitp said:
Sorry, the link was bad. I'm used to posting links in that format from another forum. Anyhow, it's fixed in the last post, and here it is as well:
http://forum.xda-developers.com/showthread.php?t=544421
Click to expand...
Click to collapse
Thanks for updating the link.
I have tried both of the CABs for the non Nokia and both make no difference if you
can't get a GPS lock. AGPS simply does not work using the latest Google maps CAB
available.
The "FF Ultimate aGPS Tweak_supl.google_Generic.cab" actually makes Google Maps
take forever to just start up after being installed and still no location is updated
indoors. Also, the phone will not snyc now with the desktop and this is after three
soft resets.
Even worse is the fact the phone now runs slow as hell. Everything takes forever
to open and is VERY sluggish.
Installed the other CAB "FF Google aGPS Settings Generic.cab" and still the same
problems. What could be the problem?
Finally got fed up with the POS CAB and uninstalled it. So far I've notice that the
phone has recovered its speed opening items and the right ones not like before
with that POS CAB which would cause all kinds of problems. Snyc now works
and so this looks like I'm back in business minus the fact I still can't get the aGPS
to work.
Oh well, you can't win them all...
AE!

[solved] GPS lags and reports position off by 300m?!

Hi all,
I did search the "General" Forum, but didn't find much. Today I tried the built-in GPS for the first time, with demo versions from copilot and Navigon mobile navigator. Weather condition was cloudy/foggy (1000m/3000ft cloud base, "Hochnebel") and it was snoming a bit. Bluetooth and WLAN were turned off. AGPS had a recent update.
Unfortunately, the system was unusable. The gps got a fix after about 10 seconds with 7 to 8 satelites in range; but basicly trouble was that it was lagging and skipping a lot. I don't mean serial communication, both programs reported position updates every second, as it's supposed to be.
But in the raw output speed jumped from 0 to 100kph every 5 seconds (I was diving 100kph constantly) and position updates were sometimes fluent but then again only every 3 seconds a new position (= 3 times same NMEA packet). Obviously this confused the nav software(s) a lot.
In addition to that the GPS position is reported incorrectly 300m to the south. I can reproduce the error constantly, If I drive NS direction, it will only report a wrong position on the street, but driving EW is not possible, it will always set the car on parallel streets and will recalculate the route constantly.
Is this a known problem on Leo and is there a fix? Obviously the intermediate driver here in the forum will help with the skipping, but not with the off-position reports.
Thanks, mc7
edit: reload agps data over 3G connection or WLAN. it seems that active sync download corrupts the agps data.

Haven't experienced anything like this myself and I was doing a 160km trip in similar conditions this past Friday so I don't think it's a known fault.
My suggestion would be to try again and if it continues get your set replaced.

Hi. A few things spring to mind from my time selling (dedicated) GPS devices.
Thick Fog/snow clouds block more of a signal than any other type of weather short of trees.
Some types of Tinted/Reflective/Heated windows (especially the type the mondeo use, if I remember correctly) can seriously affect the signal.
The angle that the device is positioned on the dashboard, and hence the angle the GPS antenna presents to the satellites is also critical.
Test the positioning on a fairly clear day, with the phone well exposed to teh sky, and no surrounding trees/houses/tall buildings, and see if the accuracy is still off. If it is, then the gps is dodgy and you should get it replaced. If it is accurate, then start looking for interference in your car.

No lag with copilot here, very accurate road positioning

ahhhh finally, solved again It seems that somehow the agps data got corrupted via activesync synchronisation. I turned off the "download via activesync" option in quickgps and reloaded AGPS data over the 3G connection. Now everything is in working order, no lagging, position accurately aquired, only a bit slow, like 10meters behind actual position. But that I had with my old diamond as well, it's not a draw back. btw, weather conditions were the same...
thanks again for your help.

AGPS has nothing to do with sync. I think you are confusing this with QuickGPS.

pedmond said:
AGPS has nothing to do with sync. I think you are confusing this with QuickGPS.
Click to expand...
Click to collapse
AGPS data (quickgps) can be downloaded via activesync in stead of over-the-air services.

Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.

loomx said:
Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.
Click to expand...
Click to collapse
AGPS comes in two forms
http://en.wikipedia.org/wiki/AGPS

loomx said:
Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.
Click to expand...
Click to collapse
Correct, that's my understanding as well. With the detail that AGPS is actually more than simple triangulation.

Nope, see wikipedia entry on agps. HTC uses satelite data/orbit information provided via internet; it stays accurate for about a week hence the weekly updates. your gps will work without this data, however, since it needs to calculate satelite trajectories by itself it will take longer to get a fix from cold start.
and if this help data was downloaded incorrectly, it obviously is possible that the receiver reports a wrong position. But, as stated, reloading the QuickGPS data and turning off activesync loading of the data solved the issue.
What you mean with triangualation is google maps. it gets the signal strength from neighbouring base stations and their cell ids and looks up their position in a large database online. with the base stations' exakt positions and the signal strength of each one, one is able to estimate the current position through triangulation; however since this method does not account for multipath propagation or reflection off wet walls or similar, it can only be taken as rough estimate.

Slow gps signal search

hi guys,
when i try to use gps (with syngic), it takes a lot of time to search satellites. when i had WM, there was an app that downloaded satellite's data every week. there is a way to have a faster signal search in android?
thanks

loscassapalle said:
hi guys,
when i try to use gps (with syngic), it takes a lot of time to search satellites. when i had WM, there was an app that downloaded satellite's data every week. there is a way to have a faster signal search in android?
thanks
Click to expand...
Click to collapse
Mine does it already, when I enable GPS, the mobile connections kicks in and I get a fix in no time

as far as i know the aGPS ( assisted GPS ) can use the network towers to make a quick location fix within a radius of 1.5 Km, but you need to have this function active.
knowing roughly where you are helps the gps to select the needed data from the satellites.
last week i got a gps fix in less then 20 sec.

k.mooijman said:
as far as i know the aGPS ( assisted GPS ) can use the network towers to make a quick location fix within a radius of 1.5 Km, but you need to have this function active.
knowing roughly where you are helps the gps to select the needed data from the satellites.
last week i got a gps fix in less then 20 sec.
Click to expand...
Click to collapse
but AGPS needs data connection

[Q] Anyone Elses GPS Aweful?

I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]

Nothing wrong with my gps. Have you upgraded to the latest firmware? Downloaded the A-GPS data (you can get this by using an app called GPS status)? Switch OFF wifi after you do, then leave it to get a full signal lock (takes up to 15minutes or so with a clear view of the sky).

toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
Make sure you are outside with a clear view of sky when you test. It can take any GPS up to 10 minutes to acquire the ephemeris information (satellite position at a certain time) and lock up. You phone cheats this by using the cellular network to provide a general location of where your are and therefore where to look for certain satellites.

thanks so much for the info guys. I had a feeling it had something to do with no cell phone band helping out. thanks!

GPS works fine here, as other have said the closer you are to the sky/window the better.

yeah..give your TF a few minutes to lock up sat positions (if you've never done this)..
this applies to most pure gps devices..cellphones can use cellular network signal to quickly locate your position but the data isn't really from gps itself.

http://forum.xda-developers.com/showthread.php?t=1088120
Hope this helps
Acid lestitious 2.0. Fugumod 2.4 800 mhz

jerrykur said:
Make sure you are outside with a clear view of sky when you test. It can take any GPS up to 10 minutes to acquire the ephemeris information (satellite position at a certain time) and lock up. You phone cheats this by using the cellular network to provide a general location of where your are and therefore where to look for certain satellites.
Click to expand...
Click to collapse
I wonder if it does the wifi cheat like maps for android phones, where it uses the known APs to determine location? I say that because when I first fired up my transformer yesterday, after connecting to wifi, I screwed around on maps and it found me inside my house in less than 30 seconds.

toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
its the reverse for me! in the same room of house i often cannot get a fix on my Optimus 2x. i use GPS Staus app. but i often get fix within 30secs. as a test i have both machines running the app next to each other and the transformer always gets regular fixes.
..... hmm just realised as i type this that i have a phone called optimus and tablet called transformer, and they both run android!!!

I get fixes with no wifi (ie: only GPS) within 30 seconds.

Quite the opposite, mine is extremely accurate. After it gets a fix on maps that little google person is standing right in my front yard in the satellite view! Better than my Droid!

Mine is almost instantaneous. Just tried it at home based on this thread and had a read in probably 5 seconds.

I have not been able to obtain a GPS lock until today when I set my location to use wireless networks. To me this is really stupid because the GPS shouldn't have to use any location settings to obtain a lock in my mind. That is if the GPS chip in the TF is a true GPS chip it should not to rely on a wifi signal to obtain a lock. If the GPS is turned on then it should lock.

I tested sygic gps navigation 11 and signal lock and quality was better than my galaxy s was pretty accurate
Sent from my Transformer TF101 using XDA Premium App

Works fine for me, apart from one minor detail. When I switch from Google Maps to another app, even for a few seconds, then the tablet has to get a lock all over again. There appears to be no way to set the GPS to keep a lock while Google Maps isn't the active program.
That, for me, makes Google Maps near-useless in a moving vehicle. Hopefully other third-party apps won't have this issue.

Google Maps is prety much useless on the Transformer for GPS navigation as a data connection is need. I have heard of people caching a route before hand but ..... Copilot Live 7 is out for android so that is one option. However if the GPS relies on a wifi signal in order to obtain a lock then it is about useless too.

toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
Gps works fine on mine....unlike my icons or Samsung...both returned

gps does use wifi to help gps locate, theres options to turn this off in settings, i went to pick up my dock today and couldn't get a gps lock while in the car with the transformer in my lap(gps status app showed 3 sats but none would lock) just lifting it up 12 inches closer to the windshield made 7 satellites pop up and instantly started getting locks
i think proximity to a window/line of sky is a big factor, and the transformer does have a true gps chip for those who seem to doubt it, also the navigation app keeps running in the background, its better to use that than google maps

No issues with gps here. The bastard finds me every time!

jadesse said:
However if the GPS relies on a wifi signal in order to obtain a lock then it is about useless too.
Click to expand...
Click to collapse
It doesn't rely on WiFi for a lock, it just uses it to allow a faster connection if you don't already have current ephemeris data downloaded. That's a limitation of all GPS receivers -- it takes a fair while to download the ephemeris data if you're out of date or have travelled a significant distance, and without it the device can't get a GPS fix.
You can think of the WiFi location system as analogous to a cellphone being able to use tower locations to help position itself while waiting for GPS ephemeris data.