Official GPS Troubleshooting Thread

[GHT]

I'm trying to open a thread where those who wish to contribute to finding a TECHNICAL solution to Palm Pre GPS issues (most likely Verizon) can collaborate in an environment uncluttered by conspiracy theories and other complaints that do not help us progress towards a solution.

Here are some guidelines I'd like to see followed for this thread:

1. No Verizon conspiracy theories, please. They may very well be doing it, but proving that or complaining about it is not the purpose of this discussion. If we happen to somehow prove that the evil Big Red empire is indeed crippling GPS, we'll be sure to let everyone know.
2. No complaining. There are a lot of other GPS threads you can use for that. We're trying to find solutions here.
3. No requests for others to file complaints with the various consumer protection agencies or with Verizon. We're not waging a legal or political battle in this thread.
4. Now that the "don'ts" are out of the way, please do tell us your testing and troubleshooting results. Don't exaggerate or make other wild claims - this erodes the quality of the data collection. Be as specific as possible about things like when your last reboot was, were you moving, what GPS program(s) were you using, how long it took to get a lock, your region of the country, the weather that day, your location services settings (Google Services on/off, auto-locate on/off, etc), and anything else you think may add to the cause.
5. No bashing others for their brainstorming or ideas (unless they violate the rules listed here.) This is a community of passionate people with passionate ideas, but we must have patience with ourselves and others who are frustrated by the lack of good answers to this problem to-date. I'm confident that we can can find answers, if not solutions, to this elusive issue. Thanks!

To start us off, here are a few things that seem to be helpful for those looking for answers:

Turning Google Services to "off" under "Locate Me Using" in the Location Services menu prevents the GPS programs from returning inaccurate results based on cell tower information rather than an actual GPS lock.

Opening VZ Navigator and either leaving it open or declining the purchase agreement often results in solid GPS locks for all programs within seconds, even after trying unsuccessfully without opening VZ Nav.

Dialing ##477# takes you to a menu where you can ask the GPS system to attempt to get a location fix.

Some folks have reported better success getting GPS to "wake up" with different GPS-enabled programs such as Send My Location for WebOS and Trapster. Google Maps seems to be the most troublesome for getting the elusive initial fix.

Rebooting the phone has been reported in some cases to improve results when attempting to get a GPS fix.

Here are my current beliefs compiled from my observations and those of others:

1. Initial lock is difficult to come by. A clear view of the sky seems to help. (duh) The GPS receivers in phones are not as powerful as those in, say, your Garmin nuvi or TomTom. They make take a long time to get an initial lock, but once they do, it should be pretty solid.
2. VZnav assists with initial lock by providing aGPS data, including satellite orbital information to the GPS unit, allowing a fast GPS lock.
3. The phone may be storing a cache of old satellite information that VZnav either updates or clears upon launch, allowing the GPS to start fresh and look for satellites.
4. Rebooting the phone also seems to clear this cache, if it exists.

So, it appears that Verizon is not crippling the GPS, but they are certainly appear to be going out of their way to make sure they don't assist it.

UPDATE: I was able to email myself GPS "results" from Nice GPS Superior today while standing in my parking lot at work under a clear sky, having cleared the list of results from within that program, and asking it to get a new set of location data. It showed the rotating progress icon for about two minutes, then told me I was about 12 miles away from where I actually was, moving at 44mph. Not surprisingly, I recognized the returned location as the last time I had used Google Maps (or any other GPS program) while driving (passenger, actually) home the day before. This reinforces my belief that there is a stored cache of GPS information on the phone, as not only did NiceGPS Superior return old results, it actually told me I was moving at 44mph! I repeated the "Get Position" function twice with the EXACT same results - exact same coordinates and same speed, which tells me that it wasn't a false result based on the position information updating, but definitely old data from some sort of cache. Now, this is no knock on NiceGPS Superior, as I have had Google Maps, Send My Location, and other GPS programs return old results in the past. I think it is a matter of the GPS system supplying its last cached data if a new fix cannot be acquired quickly.

Now, commence problem solving!

[GHT]

Sounds like some folks are appreciating an app called SimpleGPS, which will show GPS fix results on a ping-by-ping basis. From what I've read, this allows you to watch the GPS location accuracy change as the systems attempts to find your location. I've yet to try it, but thought I'd let everyone know. There is a paid version in the app catalog that allows recording of your GPS location, and a free version available through Preware.

[Cantaffordit]

fiy, good os-level discussion here. Invited them to move to your thread.

http://m.forums.precentral.net/showt...=1#post2426144

also an interesting headline article on precentral this am a out aGPS.

[Cantaffordit]

is this going to become a sticky thread?

[milominderbinder]

Posting this in all of the GPS threads...
- - - - - - - - - - - -
Please see:
http://forums.precentral.net/palm-pr...ng-thread.html

http://forums.precentral.net/palm-pr...s-problem.html

[sf_basilix]

I don't want to trample on your thread, but the link provided by cantafford it is something corbintechboy and I are working on. I can move our new posts to this thread or continue on there and just bring back our findings. Just let me know.

[mespiff]

I know that i do a few things different then a lot of people here looking for solutions but my set up is as follows

i have find me using GPS and google services both turned on
this allows what i thought was AGPS to be active when i am indoors and with the exception of google maps i belive that it aids in a quicker spot on connection.
i have the auto locate on so that aps like where is my pre will funtion in the background.


i read that if you want more acurate readings you should turn off goggle services but when i did i found that lock took longer and that some times did not happen at all -- i can live with the GPS being off when i am sitting on my couch and all i want is to hook up to weather bug quickly

a lot of what i read in these forums directs people to set these settings to the exact opposite of what i have on my phone but i have never had any GPS problems -- if i am frustrated about not getting signal sometimes i will pull out my garmin nuvi and compare and it is rare that the garmin will aquire signal when the pre will not and while the garmin is more acurate it is not that much more

[GHT]

Google Services uses tower triangulation, which gives a rough estimate of where you are. aGPS (VZ Navigator) sends satellite orbital info to the phone to allow the GPS system to lock onto a true location quickly.

[GHT]

Originally Posted by sf_basilix

I don't want to trample on your thread, but the link provided by cantafford it is something corbintechboy and I are working on. I can move our new posts to this thread or continue on there and just bring back our findings. Just let me know.

Either is fine with me. This thread is now a sticky, so it may be the one to use for reporting findings. I don't want to discourage the great work that is being done in the other thread, but a lot of what you're doing may be over the heads of most people looking for answers. I would encourage you to keep that dialog going and report significant findings here. Thanks.

[sf_basilix]

Originally Posted by GHT

Google Services uses tower triangulation, which gives a rough estimate of where you are. aGPS (VZ Navigator) sends satellite orbital info to the phone to allow the GPS system to lock onto a true location quickly.

This may be the confusing part - I think we need a resident expert on this to offer more insight.

I was just corrected the other day on this as I too thought Google Services was cell tower triangulation, but I'm not sure it is. User Mikey47 posted this link regarding Google Services:

With Google’s My Location, Who Needs a GPS?

As such, I deduced aGPS was cell triangulation, which is why VZ Nav is able to pick up a location indoors for most people.

I think there may actually be an issue with the actual GPS receiver not getting the info.

[moserjj]

I've been looking into VZ navigator app to see what is different with the GPS api call. So far, I've found 2 additional (and undocumented) parameters that may or may not make a difference. I threw together a quick GPS tester app that includes these 2 parameters but since I have only Sprint devices, it works fine.

If someone wants to test it with a Verizon device, you can get the app for free at http://j.mp/myGPSapp

You can also notice how unresponsive the GPS tracking seems to be for the first 15-30 seconds. Once you get a better lock, it seems to update every second as it should.

[Cantaffordit]

Originally Posted by GHT

Either is fine with me. This thread is now a sticky, so it may be the one to use for reporting findings. I don't want to discourage the great work that is being done in the other thread, but a lot of what you're doing may be over the heads of most people looking for answers. I would encourage you to keep that dialog going and report significant findings here. Thanks.

That's probably a good idea. They are doing stuff at the Linux level that is greek to me. But, it may translate into suggestions that a dummy like me can try on my phone. To be clear, I am not doing any of the Linux-level work on that thread. I just stumbled on it...

Ironically, my Pre+ finally started to illustrate poor accuracy (showing a location from a previous day)... but now the darn thing is working perfectly again (LOL).

And I think the fact that I used my BB Curve (at&t) hext to my Pre+ in the car over the last two days helps me realize two things:

Google Maps hasn't been updated in any useful way in a long time. Google Maps on MotoDroid is a completely different (and better) app. Google Maps on the iPhone is no better than it is on my BB (I compared my BB to an iPhone a few months before I bought my Pre+).

I think we are all are expecting different user experiences from google maps on our mobile. I want to understand how it is supposed to work from a UI perspective. So far I find it to be very crude and unintuitive. Hopefully all of this will result in someone building an app that does what g-maps does but with a better UI. SimpleGPS seems to have some great ability, because it actually found me in my house... I can't imagine how a GPS signal got to me, but...

Google maps is especially annoying when the screen goes to sleep. It seems to stop tracking the GPS signal (battery saving?) and doesn't keep pulling down maps. It has to catch up on all that when waking up the screen.

In terms of aGPS, I think I understand what it is doing. Stand-alone GPS units (Garmin, Tom-Tom, etc) vary in how fast they can get a fix based on a couple of variables that aGPS probably helps a cell phone find satellites more quickly. The GPS has to figure out where it is and which satellites it should focus on. There are three issues that slow that down on a dedicated GPS device.

1. The satellites drift enough that the GPS has to find them again. Many GPS devices have the ability to update the locations so it can narrow down how much of the sky it searches.

2. The length of time since last use. If I don't use my GPS for a week or two, it takes several minutes to get a lock. If I use it more than once per day, the lock is always less than a minute.

3. If I turn it on far from where I turned it off (I turn it off at the airport, then fly somewhere and turn in on in a rental car), it can take up to 5 minutes to find me...

So, if there are stationary cell towers that have GPS radios, they must be using aGPS to send "hints" to the phone to speed up those searches and sort out fragmented signals, etc.

Assisted GPS - Wikipedia, the free encyclopedia

So part of the user expectation I want to figure out is impact based on geography (city/country, markets with/without agps, etc), line of site (putting it on the dashboard makes a huge difference in my car - but the sun heats it up and sets off the alarm really fast), how to clear any cache, how to use the "little blue dot" to find/center my location, etc. etc. etc.

I can do stuff like that in spite of my lack of linux knowledge. I just wish I could start with knowledge as to why My Pre+ seems to work so well (as did the first two that were replaced by my current Pre+). Is it because of where I live, or something about my particular phone?

Hopefully I will have some business travel where I can test it. I was in New Jersey two weeks ago, and it was working fine - but I was playing with Latitude and didn't watch it every second. I was just forcing an update in Latitude ever 10-15 minutes to see where it thought I was. It was always close enough and agreed with my BB Curve. Next trip I will watch it more closely... in Google Maps and SimpleGPS...

Is this making any sense? Comments, please.

[Cantaffordit]

Originally Posted by sf_basilix

This may be the confusing part - I think we need a resident expert on this to offer more insight.

I was just corrected the other day on this as I too thought Google Services was cell tower triangulation, but I'm not sure it is. User Mikey47 posted this link regarding Google Services:

With Google’s My Location, Who Needs a GPS?

As such, I deduced aGPS was cell triangulation, which is why VZ Nav is able to pick up a location indoors for most people.

I think there may actually be an issue with the actual GPS receiver not getting the info.

See my post above. I believe aGPS is a way to get info about GPS satellites to the phone so they can find the right satellites more quickly from tower radios that are stationary... Is that basically correct?

Assisted GPS - Wikipedia, the free encyclopedia

That article about Google Location services is from 2007, and it makes sense based on what I saw on my BlackBerry and Centro in the two+ years before I got my Pre.

I'm assuming that I have really good exposure to satellites here because I get great performance on both BB and Pre+ with the My Location service turned off. However, I think that logging in to Latitude must turn it back on because some of the flaky "caching"-like behavior will show up when I wake up the phone, and then correct itself in 10 or 20 seconds...

And that explains the difference between Google location services and tower triangulation. I had thought they were the same, too.

And it explains why Google Maps appears to work so much better on android, since Google has a vested interest in making that OS work well...

[sf_basilix]

Originally Posted by moserjj

I've been looking into VZ navigator app to see what is different with the GPS api call. So far, I've found 2 additional (and undocumented) parameters that may or may not make a difference. I threw together a quick GPS tester app that includes these 2 parameters but since I have only Sprint devices, it works fine.

If someone wants to test it with a Verizon device, you can get the app for free at Palm USA | Palm webOS Applications | Mobile apps that go further.

You can also notice how unresponsive the GPS tracking seems to be for the first 15-30 seconds. Once you get a better lock, it seems to update every second as it should.

since you have a Sprint Pre, could you assist us in this side-bar thread for a sec?

http://forums.precentral.net/palm-pr...zon-gps-3.html

We're trying to compare before and after gps lock on modinfo, ps and netstat. We're also trying to figure out which app sprint calls to start up their signal locking. For VZ it's VZNavigatorService. This app runs when the phone boots up and is activated upon VZ Nav startup, but want to find the Sprint equivalent to see if we can port it over to the VZ phone.

Also - I assume palm-launch would also be on the phone, but it doesn't appear to be. Are you familiar with how to launch apps via CLI? I'm trying to dump debugging info to figure out what's happening with the VZ Nav startup.

Thanks

[moserjj]

Originally Posted by sf_basilix

since you have a Sprint Pre, could you assist us in this side-bar thread for a sec?

http://forums.precentral.net/palm-pr...zon-gps-3.html

We're trying to compare before and after gps lock on modinfo, ps and netstat. We're also trying to figure out which app sprint calls to start up their signal locking. For VZ it's VZNavigatorService. This app runs when the phone boots up and is activated upon VZ Nav startup, but want to find the Sprint equivalent to see if we can port it over to the VZ phone.

Also - I assume palm-launch would also be on the phone, but it doesn't appear to be. Are you familiar with how to launch apps via CLI? I'm trying to dump debugging info to figure out what's happening with the VZ Nav startup.

Thanks

Sure I can help out. I'll try and report my findings soon. I'm familiar with the CLI for dealing the device - logging, installing, etc.

[mespiff]

this thread is exactly how this issue needs to be addressed -- thanks so much. i was getting tired of the non- productive threads that were garnering all of the attention --THANKS

[jhodnettejr]

i've been posting on most the gps threads. I've pinned this issue down to apps (even vz navi on rare occasion) not wakiing the gps chipset... I dl'd and used moserjj's app....as always, I have to try multiple apps to wake my gps....simple gps too.... Usually it takes 3 different apps to "jump start" the gps

[ScorpionSoul]

A thought just occurred to me, so I did some checking around on other forums about GPS. My thought matches with what I found, so hopefully this isn't something that's been overlooked and creates a giant "Doh!" moment

Anyway, battery issues being what they are, a lot of people (myself included) have a tendency to keep 3G and/or wifi turned off when not in use. And I figured that, since the Pre's GPS is trying to get aGPS data from cell towers and standard GPS data from satellites, that 3G and/or wifi are not required for the GPS to function. From what I've read, this is true... but GPS acquisition will be significantly slower without it (this, I don't know why.. it's just what I read).

Anyway, more to the point. I went back outside and repeated someone's earlier suggestion (which I had success with) and tried opening up Trapster. Couldn't get a lock after several minutes. Same with GPS Dashboard. Then I noticed that I didn't have 3G or wifi enabled. Did a quick reboot, turned on wifi and had a lock in both programs in under 10 seconds. Another quick reboot with 3G instead of wifi and had a lock again in around 10 seconds.

So, since the guys who are spending all their free time digging through code that makes no sense to me have mentioned looking for something that would trigger the aGPS service... maybe try looking at the 3G/wifi aspects and see if there's something there. As I said, hopefully this is just my lame attempt at a suggestion, rather than a troubleshooting oversight that results from trying to save battery power.

Anyway, it's just a thought... feel free to tell me I'm way off mark and let the people who know what they're doing handle it

*edit*

And in case it's useful information, I have never (not even once) opened the VZNav application on my phone...

[sf_basilix]

Originally Posted by jhodnettejr

i've been posting on most the gps threads. I've pinned this issue down to apps (even vz navi on rare occasion) not wakiing the gps chipset... I dl'd and used moserjj's app....as always, I have to try multiple apps to wake my gps....simple gps too.... Usually it takes 3 different apps to "jump start" the gps

good to know. I'm working on a script that will try to obtain gps info within the kernel - maybe what I'll do is bombard it with multiple requests, rather than one, and see if that wakes it up any better.

[mespiff]

Originally Posted by jhodnettejr

i've been posting on most the gps threads. I've pinned this issue down to apps (even vz navi on rare occasion) not wakiing the gps chipset... I dl'd and used moserjj's app....as always, I have to try multiple apps to wake my gps....simple gps too.... Usually it takes 3 different apps to "jump start" the gps

you know for the most part i would have to agree with you - i have been saying the same thing for months now. Rare aps deffinately work better at waking up the chipset --but it is something with how the GPS information comes awake and is shared that is the issue. At least that is what i see. Also I think that a lot of people base whether or not there GPS is working on what Google maps is showing them -- that is a poor base line . google maps does not seem to enteract with the webos very well and really it just seems like very little effert went into the design of this ap for anything other than android phones -- i really cannot blame google for that but again i say that i feel that there should be other aps consulted to see if the GPS is active.