Database Develop

WAZE Free Nav Software

Has anyone else checked out Waze.com free open-source navigation and mapping software? Looks really cool.
Jamie

I started playing around with this software yesterday, I must say that its pretty brilliant. Hopefully it catches on with enough people and it gets popular.

i love this new app i was amaze to hear turn by turn and speed reading very good app just wish the police option was near me and not 900 miles away

Oh! There's more to this than just playing Pac Man with my car?

looks pretty cool, I'm gonna try it out!

It is THE killer app for all paid navigation software.
IF! the provider can stay alive long enough it will catch up globally.
Then within 5 years it will be the ONLY navigation app left.
The disadvantage is how to reach as much people possible and convince them to install. Then get in the car every day and turn it on and start driving.

I DL'd it and played with it this weekend. It does have huge upside, however, it will not be a threat to navigation software. They even say that Waze is about commuting and traveling around areas you normally travel. The software helps you inteligently see what might be affecting your commute and to route you to your location using real time traffic data.
A real world example, regular navigation software iGo, Garmin, etc, will help you find a grocery store. Where Waze will get you into the fastest checkout line, based on the speed of the customers checking out, while you were still shopping for milk. I know how to get to my work, I also know that there are several alternate routes, waze is supposed to be able to tell you which one would be faster on any given day based on real time info from other drivers.
I live in the Cleveland, OH area. We get Lake Effect snow storms. These snow storms can be very small, but very intesnse. It is not uncommon for a stretch of highway a mile long to be in near blizzard conditions, and it is sunny and clear all around. You have no idea that you are going to run into this storm until you are in it. Waze could detect the sudden drop in speed, and advise others that there is an issue, thus allowing us to pick a different route.
If you hadn't noticed I am excited by the potential. They have some bugs,the software is o.k., but it needs more developing. I was driving over the weekend and was notified of an accident 300+ miles away. However those issues are being worked on.

It has real promise
boufa said:
I DL'd it and played with it this weekend. It does have huge upside, however, it will not be a threat to navigation software. They even say that Waze is about commuting and traveling around areas you normally travel. The software helps you inteligently see what might be affecting your commute and to route you to your location using real time traffic data.
A real world example, regular navigation software iGo, Garmin, etc, will help you find a grocery store. Where Waze will get you into the fastest checkout line, based on the speed of the customers checking out, while you were still shopping for milk. I know how to get to my work, I also know that there are several alternate routes, waze is supposed to be able to tell you which one would be faster on any given day based on real time info from other drivers.
I live in the Cleveland, OH area. We get Lake Effect snow storms. These snow storms can be very small, but very intesnse. It is not uncommon for a stretch of highway a mile long to be in near blizzard conditions, and it is sunny and clear all around. You have no idea that you are going to run into this storm until you are in it. Waze could detect the sudden drop in speed, and advise others that there is an issue, thus allowing us to pick a different route.
If you hadn't noticed I am excited by the potential. They have some bugs,the software is o.k., but it needs more developing. I was driving over the weekend and was notified of an accident 300+ miles away. However those issues are being worked on.
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We are both excited at the potential of this concept, but I think it could easily replace TomTom or Igo, IF Waze becomes widely and consistently used. It sounds like you think Waze is less useful when navigating to somewhere you haven't been before, but as long as other people on that route are also contributing data, Waze will still be more useful than even paid traffic subscriptions, because it is real time data from the road, not from observers. We all will need to use it all the time for it to live up to its promise.

I agree that more people need to use it. I was excited on a trip over the weekend to pass by someone going the other way... their icon showed up on my phone. Lots of cars around, no way to tell which one it was exactly, but kinda cool none the less.
The reason I think it is more of a commuter app than a navigation app it 2 things, 1) that is what it says on their FAQ page, and 2) I drove from Mentor, OH to Canton, OH a trip of about 90 miles. I knew close enough to where I was going, that I did not need navigation software, so I turned on waze and let it data collect... (It is important to let it collect data whenever possible, especially until the user base gets bigger)... the onscreen map showed only the map for the last "tile" i was in, and only showed a blank white screen for the space in front of me. On the way home it showed all of the map for the areas I was in on the way down. Now, I did NOT have it giving me directions, so that may have been the issue.
It was wet and slick, and we did see and accident on the other side of the road, a car slid off a curve on an exit ramp. I was impressed that it only took 3 or 4 presses of the screen to report it!

Cool
Hi there fellow Buckeye! I'm originally from Hubbard, a speck on the map north of Y-town.
I still believe that if we can get a large and diverse enough of a user base, we won't need to pay TomTom or Igo for maps or traffic data anymore.
BTW, have you had any trouble getting your GPS signal lately? I haven't been able to get a signal at all since yesterday. Prior to that it was nearly instant. I'd normally blame my device, but I know 2 others here in ATL who were having the same issue.

Can't say that I use the GPS that often to notice. As for Waze, I agree, there are a couple of people who drive around in my area that use it, it pops up. The software needs some significant development yet... but I am an eager early adopter. The key would be to get the truckers to use it... they are everywhere.

It's working again
Not sure what happened. It was wierd becuase one of the things I love about this program is how fast I get a lock. It is almost instant. With Igo sometimes it takes minutes to get a fix.
Thats a great idea about the truckers, btw

How bad is the GPS?

im considering buying this phone,but i hear there's problems with the GPS. my current phone has a great GPS receiver and i use it a lot for day to day navigation.How much will i be disappointed if i were to expect the same from the galaxy s?

http://forum.xda-developers.com/search.php?searchid=42858169

Here in holland I have no problems with the GPS reception...

Personally, I found that straight out of the box the gps was dreadful, but an hour later after I did the simple gps fix, it navigated me on a hundred and fifty mile round trip with no problems at all.
The fix is simple and easy and takes literally no skill. When you take your sgs out of the box, see if the gps works for you, then try the fix. If there is still no joy then take it back and say the navigation is busted and you want a different handset.
I'd certainly say its worth trying at least. Chances are can get it working and everything else that you like about droid is better on the galaxy .
It's worth remembering that the gps is not battery friendly and you'll need a potent (2A output)car charger to keep you running on the move.
Sent from my GT-I9000 using XDA App

Basically, in summary:
1) In late firmware, the lock is quite quick, especially compared to car GPS units. Maybe not as fast as some other phones, but fast enough. Certainly faster than my Garmin Forerunner
2) The accuracy boundaries on this phone are wrong sometimes (at least in XXJM5), but this may be a bug in that specific pre-release.
3) With JM5, the unit seems to only lock onto 8 satellites max, but, some people are saying apparently newer firmware's are locking onto more
4) People are complaining of issues getting locks when moving with the unit. However, I've experienced this on ALL GPS units I've owned. AGPS should help with this though (but I've never tested initial lock whilst moving except in a firmware where GPS was 100% broken for me).
5) In some cases, the GPS goes skitzo, this might be fixed in later firmwares
6) Finally, sometimes the track is a bit off to the side, and doesn't handle cornering well.. This is likely related to (2). But this makes it useless for fitness at the moment
Anyway, the GPS is usable, but there are serious accuracy problems with it still. Samsung has said that they are working on optimising GPS for a September update. My best advice is wait until then, because if it isn't fixed in September, the possibility that it is due to poor hardware design seems to grow significantly..

thank you for your valuable input,this forum really is the best on the internet.I'm gunna be buying it next month anyway,so lets see if the update fixes the GPS or not.To be honest,theres no other phone that can match it,so theres no alternative to this phone even if the GPS IS dodgy

The GPS sucks so hard that I'd rather use a regular map for navigation.

My Galaxy S has no gps problems. The first time i went out from house to check GPS accuracy I got GPS signal after 3 seconds. It's stable in 100% cases.

Acquiring signal is not the issue. I don't understand why people keep comparing signal to accuracy. it's not the same thing.

Exactly, there are people in other topics that are just inflating the whole issue, their claims are way exaggerated, and the original issues has already been fixed on newer firmwares, yet they refuse to accept it.

AllGamer said:
Exactly, there are people in other topics that are just inflating the whole issue, their claims are way exaggerated, and the original issues has already been fixed on newer firmwares, yet they refuse to accept it.
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Go for a 20min jog then and show a track of your perfect GPS. I have a lower standard than many of them, but all tracks I saw lost lock excessively at some point or another..
I haven't tried it myself, but can on tuesday.

damn,so many different opinions on this issue.also not being able to track my runs is a BIG minus but still not a deal breaker.day-to-day city navigation is a must though.

It's just as simple as that - you don't check gps functionality just by its fix time. you put it in your car, and start driving - if it's accurate (highly unlikely), gewd. if not - go back here and whine.

kingofkings2603 said:
damn,so many different opinions on this issue.also not being able to track my runs is a BIG minus but still not a deal breaker.day-to-day city navigation is a must though.
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The big problem is that many of them seem to be testing quickly from their chair.. There is overwhelming evidence that the GPS doesn't work accurately, but barely any showing it does.. In fact, in one case, I saw someone claim the unit was working perfectly, but the track they showed was on a straight highway, and was fluctuating excessively between both sides of the highway. And the most vocal of those who claims it works perfectly don't seem to be posting logs..
There is also some confusion between whether it is "fitness grade" or "car grade". Car navigation GPS can snap to tracks, and has more room for accuracy errors, because it can assume you always exist on the closest road, and if you use directions, it can assume you took the correct turns when it told you to do so (and correct itself a bit later). That's what most car units seem to do, and it helps compensate for most inaccuracies. It can lead to a bit of pain though if you make lots of turns, some of which aren't correct. Some people are possibly happy because they have used dedicated car units before which suck (some navman's take at least 5 mins to get a basic lock, negating any benefits of having them), but, since some phones offer better directions apparently, people are complaining it should be better.
Fitness grade requires MUCH higher resolution to be usable, because the distance is shorter (generally), and if your GPS veers off course, it gives you a false indication of jogging distance. Garmin forerunners feel generally like they are within 1 or 2 meters a of the time (but occasionally veers off 3), but from what I've observed standing still, the flaws may be less visible when moving, but simply appear as slightly off course.
Then there are those people who stare at the SNR/locked satelites for hours at end without checking whether the long/lat is actually correct, or the accuracy boundary (they see 5m accuracy, but don't actually check if it is accurate within 5 meters). I was one of these, until I realised that the accuracy boundary was wrong..
Part of the issue also comes down to firmware though. People are using pre-release/leaked firmware (which might not even be complete) and are judging the GPS quality based on that. No comment needed except, don't assume that Samsung aren't working on fixes because there is no fix in pre-release firmware.
I haven't properly tested either though personally because I use a forerunner for jogging (waterproof), and since I fly, I prefer to use maps to understand locations better. I did notice though that leaving my phone on my desk for a long period of time sometimes allowed the signal accuracy boundary to not include me (ie, allow a position of 20m away from me, but show 5m accuracy) intermittently. And this might explain the fluctuations in position many others have gotten..
Either way, it is debatable. The biggest issue is that the assumption so far is that everyone got exactly the same hardware, and exactly the same revisions. But the other problem, is that GPS quality is open to opinion, because in some areas, roads are so far spread out that even inaccurate GPS works fine for driving. It really depends on your needs. But the facts are, the accuracy of the GPS isn't worth debating anyway currently, because Samsung have already told us they are "optimising" the GPS in Sept, which may make this unit as good as a garmin forerunner anyway. All any of us can tell you as that we'll know the TRUE potential of the unit after the september patch.
But for me anyway, I think the GPS is fine (I don't need perfect accuracy, even if I needed this as a fallback in a plane)

The GPS is bad to the point of being unusable for car navigation or fitness tracking. Yes you may get a lock in GGps test but when moving the reported location is all ov
er the place.

andrewluecke said:
Then there are those people who stare at the SNR/locked satelites for hours at end without checking whether the long/lat is actually correct, or the accuracy boundary (they see 5m accuracy, but don't actually check if it is accurate within 5 meters). I was one of these, until I realised that the accuracy boundary was wrong..
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Click to collapse
Case in point to illustrate what andrewluecke is trying to explain here about the accuracy not being exactly...well, accurate. Take a look at the attached screenshot. My GPS had a great fix with accuracy of 5m (the best it's able to report), stable for a few minutes, everything was working perfectly. Or so it seems. Except for the slight problem that I was actually standing where the red dot is... There's no scale on the screenshot, but it's a good 30-40 meters off. And that's quite common for me.

Case_ said:
Case in point to illustrate what andrewluecke is trying to explain here about the accuracy not being exactly...well, accurate. Take a look at the attached screenshot. My GPS had a great fix with accuracy of 5m (the best it's able to report), stable for a few minutes, everything was working perfectly. Or so it seems. Except for the slight problem that I was actually standing where the red dot is... There's no scale on the screenshot, but it's a good 30-40 meters off. And that's quite common for me.
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Exactly Case_. The point of the accuracy measurement is to say "you are somewhere within this range". But, with the Galaxy S, it isn't, and that shouldn't happen, at least not as often as it does (except maybe at the beginning whilst obtaining a lock"). Professional systems have something known as RAIM and FDE which detect when the accuracy may be incorrect due to external factors (such as shonky satelite, or serious atmospheric interference). But this happens a LOT, and I would have thought it affects GPS units equally (unless the Garmin forerunners in fact DO ship with fault detection, which could explain it, in which case, Samsung should implement fault detection and exclusion too, to make it usable).
Anyway.. What I am trying to say is summed up easiest with Case's post.

Fatherboard said:
Acquiring signal is not the issue. I don't understand why people keep comparing signal to accuracy. it's not the same thing.
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It most certainly is an issue. It takes a minute or longer to acquire a lock in some cases despite stationary and clear line of sight.
The people who stomp their feet with "The GPS is fine" are no different than the iPhone4 users who claim there is no attenuation in their phones.

In my case with the DDJG4 update, I see some minor issues.
Once in a while when I am at home (indoors with no visible satelites) my location shifts from bangalore to toronto. All my stuff changes to that. It looks like AGPS is not turned on or buggy becuase 80% of the times it works well. Does anybody else face the same problem ?
So when my phone takes me to toronto, i restart the phone and everythng is back to normal
SOmetimes, the location service fails to find where I am and shows Toronto in Google website. Is there anyway to avoid this.

It's just like what most people say, you can get a fix, and GPS seems fine. Try to use it, and it's a whole different story.
Somebody on the forum posted a link of a run, where the SGS GPS went everywere but on the straight line, it even made a hilarious loop. Too bad i can't find it.
People need to stop saying "Firmware updates fixed it already" as that's just not true.
Hah, there it is, posted by sjdean.
Desire, and SGS GPS.
http://maps.google.com/maps/ms?ie=U...52.48542,-1.742063&spn=0.014138,0.045319&z=15
http://maps.google.com/maps/ms?ie=U...=52.48082,-1.761761&spn=0.01414,0.045319&z=15

Benchmarking GPS Performance - Brainstorming

Ok..this is going to be a little long-winded so bear with me.
So there seems to be a new fix posted for gps every other day, some are just snake-oil while others might actually be doing something. The problem is how to tell what is working and what is not...and to what degree. Trusting the word of some guy on a forum with 200 posts is NOT the answer. What we need are some objective tests that produce quantitative data. It would also be nice to objectively compare our device's performance to the performance of other android devices out there too...to get an idea of what a realistic gps performance expectation would be.
So far MyTracks seems to have been the best approach but it's still a very poor method for several reasons:
The software acts as an abstraction layer - it's unknown what kind of filtering may be occurring here.
The data is only meaningful to the originator; we don't know which street(s) you were really on.
At best only 1 dimension of the error is preserved; we might be able to assume you were driving down street X, but how do we know how far down the street you actually were when the sample was captured?
Bottom line, there is no way to programmatically extract quantitative results.
I've got half of the solution: Collect a series of samples from a stationary position and collect lat/lon/alt/time, reported gps accuracy, number of satellites used, time to lock, device make/mode, device uptime (to weed out the "I rebooted and it works!" phenomenon) etc.
With this data we can calculate things like jitter, deviation, acquisition latency and all kinds of other interesting things.
I know that sounds like lots of work, but I've already done all of the above (scroll down to the bottom to read more about that) and for the most part the data collection and result presentation components work. The problems I am running into are related to the details of how the above data maps to real world performance.
So let's talk about some potential algorithms:
1. Deviation
This was my first hope as a solution; grab bunch of gps coordinates and use the lat/lon positions along with reported accuracy to get a centroid location. Then using the centroid, calculate the distances between each point and the centroid to measure accuracy. In theory, if the distribution was random, this would work. In practice however, I found that:
A - You get A LOT of duplicate points that throw off the statistics.
B - Even if you throw out duplicates, the coordinates you get are usually very close to one another, in spite of being far from the true location. In hindsight, I think that should have been obvious. Oh well.
In any case, let me illustrate:
I took 30 samples sitting in front of my office. The distribution looks like this:
http://maps.google.com/maps/api/staticmap?size=512x512&maptype=hybrid&markers=color:blue|label:1|37.280015489448,-121.943445407709&markers=color:blue|label:2|37.280015489448,-121.943445407709&markers=color:blue|label:3|37.2799150689755,-121.943469689324&markers=color:blue|label:4|37.2798287737251,-121.943507481842&markers=color:blue|label:5|37.2797409130025,-121.943532462122&markers=color:blue|label:6|37.2796490544446,-121.94354159922&markers=color:blue|label:7|37.2796117648545,-121.943468886907&markers=color:blue|label:8|37.2796034813727,-121.943455640717&markers=color:blue|label:9|37.2795946561935,-121.94344227994&markers=color:blue|label:10|37.2795861462627,-121.943431154687&markers=color:blue|label:11|37.2795786087998,-121.94342342341&markers=color:blue|label:12|37.2795720667083,-121.943418240036&sensor=false&sensor=false
And the centroid I calculated from these looks like this:
http://maps.google.com/maps/api/sta...7,-121.943465819874&sensor=false&sensor=false
Looks pretty good so far right? Not even close. You can almost predict where the gps will say I am going to be next just by looking at those points. Unfortunately, there's no data there about where I actually am. I was actually standing outside of the building, smack in the middle, which is about 30 meters south of the closest sample I got.
Which brought me to idea #2:
Measure reported accuracy, sampling frequency/jitter, time it took to acquire the initial lock and call it a day.
Which brings me here - I'd like to do this right and so I'd love to get anybody's feedback on what kind of algorithm to use to characterize gps performance.
Also, if anybody wants to take a peek at whats been done so far, here's a link to a page with the latest version of the android client. Just install it and start it up. It will pop up and error if it can't connect to the server and the server does go down from time to time, so if you get a connection error, try again a little later. The other thing to be aware of is that I enforce the "stationary collection" rule by monitoring the accelerometer. When you hit start you will have 3 seconds to put your phone on a table or the sidewalk or somewhere else that isn't moving. Once the collection starts, it will monitor GPS until it gets 30 samples. You can cancel at any time by moving the phone. If any samples were collected, they will be uploaded and you will get an option to view the results. The results aren't too terribly meaningful for now, but there are a couple interesting statistics there and you will be helping me out by stress testing the server. Feedback appreciated!
Thx

The only problem is I believe there may be some hardware variation. I've read some posts where they took two completely identical stock phones and got completely different results.

I don't see a problem with stationary data. It will always jump around. That's hardware. The hardware cannot accurately track anything less than 10 meters.
I'm more worried about why it's jumping around and losing accuracy when it's in motion.
I would make a data collection for TTTF , satellites in view, satellites with fixed, signal strength (SNR), bearing, hasAlmanac(), hasEphemeris() and accuracy.
I was thinking of writing an app but I really don't have the time for it. I have a bunch of projects lined up and really won't see any real free time until a month or two. I program for a living and currently have a private android application that uses GPS that I wrote for my clients. It's a shame the GPS is borked with the Galaxy S because I was going to use it to market my application. I have to resort to the Xperia X10. My interest in fixing the GPS is both personal and business related.
Regardless, if you need any help, let me know.
PS: I believe we need a program to really compare our "fixes" and narrow down what changes makes things better and worse. I would like to get to the point where we can calculate: X # of satellites with an average of Y dbHZ of signal strength gives you Z% accuracy

ThisWasATriumph said:
The only problem is I believe there may be some hardware variation. I've read some posts where they took two completely identical stock phones and got completely different results.
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I dont really think that the variations are hardware related, at least I've not seen any solid data to support that assertion. Different results, even wildly different between two identical phones is expected to some degree...theres too many variables involved to directly compare two phones and expect to get identical results, even side by side. For instance, reboot one of the phones and try again. The rebooted phone will have much better performance. If we get some averages based on device and software version / configuration with a large number of samples behind it, actual differences should emerge from the noise. In any case, if there truely is a hardware problem, that will probably also be discoverable as an abnormally high standard deviation compared to other devices.

CLShortFuse said:
I don't see a problem with stationary data. It will always jump around. That's hardware. The hardware cannot accurately track anything less than 10 meters.
I'm more worried about why it's jumping around and losing accuracy when it's in motion.
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Click to collapse
In theory, there shouldnt be any functional difference between a moving receiver and a stationary one. At least over relatively short distances. Yes one will be cross cutting various geometric relationships with the satellites, but they are so minute that its a moot point.
On top of that, benchmarking while moving introduces two problems:
1 - Telephone poles, buildings etc. Will periodically obstruct the signal introducing an error that cannot be subtracted out.
2 - As mentioned above, there is no known point of origin. One of the consequences of that is that the conditions surrounding the data collection of user A can vary wildly from those of user B. In essence you stop measuring performance alone and start measuring performance plus the dynamics of the neighborhood. With a stationary position at least you know that your gps shouldnt be showing you moving.
From my own testing, I can say that the Captivate typically does not even calculate stationary locations correctly, as seen in the links posted above. Sadly the error signal bears no obvious relation to the true origin. And although there is a definite pattern I don't know how to analyze that pattern. I'm humble enough to admit that I'm not smart enough to figure it out. Hopefully somebody else here is though At the very least, I think that the error patterns generated from a stationary position are a solid basis for a standard test.

You should try cognition 2.2 with CLShortfuse's jupiter tweaks. For the first time I was driving 55mph with 9-11/11 sats locked on the whole time, kept an accuracy of 5-10 meters and it accurately reported my speed dead on with my speedometer. I'm pretty satisfied with the performance right now.

Have you done any tests at a benchmark site to see how accurate it is? I have been at a benchmark site one day and gotten really accurate results, only to return on another day and have trouble getting within 300 ft. accuracy. And this was done with a "real" GPS.... I think that it is going to be difficult to get good results with a smart phone acting as a handheld GPS device. Maybe I am wrong ..... I'm no engineer or programmer...
Sent from my custom EVO PC36100 Using XDA app

halfhp said:
From my own testing, I can say that the Captivate typically does not even calculate stationary locations correctly, as seen in the links posted above. Sadly the error signal bears no obvious relation to the true origin. And although there is a definite pattern I don't know how to analyze that pattern. I'm humble enough to admit that I'm not smart enough to figure it out. Hopefully somebody else here is though At the very least, I think that the error patterns generated from a stationary position are a solid basis for a standard test.
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I haven't taken a look at your program but collecting mass amounts of information is a start. We can draw a correlation between signal strength, # of antenna and accuracy.
There is another option, that I believe would be best to identify the underlying issue. Have different Android GPS units side by side both running the same application, and have them report data for each satellite (based on PRN). They SHOULD be identical (azimuth, elevation and if possible, the reported time). Also, we would check the system times and see if they are synchronized.
According to Garmin:
Sources of GPS signal errors
Factors that can degrade the GPS signal and thus affect accuracy include the following:
Ionosphere and troposphere delays - The satellite signal slows as it passes through the atmosphere. The GPS system uses a built-in model that calculates an average amount of delay to partially correct for this type of error.
Signal multipath - This occurs when the GPS signal is reflected off objects such as tall buildings or large rock surfaces before it reaches the receiver. This increases the travel time of the signal, thereby causing errors.
Receiver clock errors - A receiver's built-in clock is not as accurate as the atomic clocks onboard the GPS satellites. Therefore, it may have very slight timing errors.
Orbital errors - Also known as ephemeris errors, these are inaccuracies of the satellite's reported location.
Number of satellites visible - The more satellites a GPS receiver can "see," the better the accuracy. Buildings, terrain, electronic interference, or sometimes even dense foliage can block signal reception, causing position errors or possibly no position reading at all. GPS units typically will not work indoors, underwater or underground.
Satellite geometry/shading - This refers to the relative position of the satellites at any given time. Ideal satellite geometry exists when the satellites are located at wide angles relative to each other. Poor geometry results when the satellites are located in a line or in a tight grouping.
Intentional degradation of the satellite signal - Selective Availability (SA) is an intentional degradation of the signal once imposed by the U.S. Department of Defense. SA was intended to prevent military adversaries from using the highly accurate GPS signals. The government turned off SA in May 2000, which significantly improved the accuracy of civilian GPS receivers.
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rtdrumz said:
Have you done any tests at a benchmark site to see how accurate it is? I have been at a benchmark site one day and gotten really accurate results, only to return on another day and have trouble getting within 300 ft. accuracy. And this was done with a "real" GPS.... I think that it is going to be difficult to get good results with a smart phone acting as a handheld GPS device. Maybe I am wrong ..... I'm no engineer or programmer...
Sent from my custom EVO PC36100 Using XDA app
Click to expand...
Click to collapse
I have neither used nor heard of gps benchmark sites - do you have any that you've used that you recommend?
I'm fully expecting the variance you are talking about, but I also believe that the variance is there because of measurable variables...it's just a matter of identifying enough of those variables to make the results understandable. For example, we know a reboot can temporarily fix gps issues so we wouldnt want to compare the gps results of a device that was just rebooted with the results of one that has been running for days.

CLShortFuse said:
There is another option, that I believe would be best to identify the underlying issue. Have different Android GPS units side by side both running the same application, and have them report data for each satellite (based on PRN). They SHOULD be identical (azimuth, elevation and if possible, the reported time). Also, we would check the system times and see if they are synchronized.
According to Garmin:
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Click to collapse
I briefly started down that road by grabbing the raw NMEA sentences but quickly abandoned that path due to the volume of data being pumped. Maybe I should take a second look.
Regarding the dual phone test, thats an interesting idea. I wouldnt have expected the clock times to vary at all. I'll check into it!

Also, for whoever is interested, here is a link to some results generated by the app in progress:
http://www.halfhp.com:8080/ggs/results/show/1?mode=mobile
It only shows a small subset of the data collected, but you get the general idea of what I'm going for.

I disabled the automatic time sync. I'm going to look for an app to synchronize my clock. I'm going to disable AGPS and take a test run. It could be wrong timing that makes it unable to grab a fix
WOW, talk about a difference. I disabled time sync and I used an application called "Micro Second".
Clock difference: 5.41638 seconds
That GPS trailing/sliding issue seems about 5 seconds as well......

CLShortFuse said:
I disabled the automatic time sync. I'm going to look for an app to synchronize my clock. I'm going to disable AGPS and take a test run. It could be wrong timing that makes it unable to grab a fix
Click to expand...
Click to collapse
Shouldnt the chip be keeping track of it's own time? One common use of gps is to provide a time signal accurate to the microsecond. As far as I know, all gps devices are capable of that kind of accuracy - they have to be in order to work at all, they just dont advertise it because many dont provide a physical interface to the PPS necessary for external devices to utilize it.

halfhp said:
Shouldnt the chip be keeping track of it's own time? One common use of gps is to provide a time signal accurate to the microsecond. As far as I know, all gps devices are capable of that kind of accuracy - they have to be in order to work at all, they just dont advertise it because many dont provide a physical interface to the PPS necessary for external devices to utilize it.
Click to expand...
Click to collapse
"Should" and "does" aren't the same thing. That's under the assumption that the NMEA data is provided by gps device itself. I don't believe it is. I think the GPS device gives raw satellite data and the driver wrapper calculates NMEA data back to Android.
Also, factoring the clock desync from the correct atomic-based time should be in the data.

CLShortFuse said:
"Should" and "does" aren't the same thing. That's under the assumption that the NMEA data is provided by gps device itself. I don't believe it is. I think the GPS device gives raw satellite data and the driver wrapper calculates NMEA data back to Android.
Also, factoring the clock desync from the correct atomic-based time should be in the data.
Click to expand...
Click to collapse
I think you might be at least partially right as far as the NMEA sentences being generated outside the chip. I did a little bit of digging on the BCM4751 chip and it appears that the protocol used is MEIF, which according to the internet is a proprietary nokia protocol. I havn't found a description of the protocol yet, but I would think that it offers at least the same amount of data that NMEA offers, meaning time is kept on-chip as expected. I just cant imagine the system clock being anywhere close to useable for such a time sensitive calculation as gps triangulation. I'm gonna keep looking though.

Something else to consider guys...
I've seen lots of people referencing GPS accuracy when in motion versus standing still. I'm not so sure that all of them are complaining about what they think they're complaining about.
My primary vehicle is a motorcycle. For crappy weather, I've got a Jeep Wrangler with a fiberglass hardtop. In both cases, the phone has no sheet metal between it and the sky. And in both cases, the GPS appears to track just fine. It may not show me in the proper lane of a multilane highway, but it at least always shows me on the right side of the road, and it never lags behind my actual position. Nor does it suffer from any 'inertia' problems. When I turn, so does it. When I stop, it does too.
Now... I'm out of town at the moment on a business trip and am driving a rental car - one with a fixed sheet metal roof (no sunroof either). Since my GPS had been working at home, I was expecting it to work over here as well. Wrong! It takes forever to get a lock, and when it finally does, it drifts in and out of lock. And as I'm driving along, it's sometimes as much as 5 seconds behind me. Or sometimes along side me on a side street. Or when I stop it keeps going. You know, all the crap that everybody's been complaining about.
So. Is it a setting issue, a driver issue, or is it a problem with the hardware? I can't tell you. But what I can say is that when there's any significant metal obstruction between the phone and the sky, the GPS is hit and miss... mostly miss.

Droid 3 GPS Issues

I have had continuous issues with the Droid 3. One of my biggest issues is that the GPS seems completely unstable. I have tried turning on/off GPS options, etc...
Weather I try to use Google Maps or another application such as Endomondo, it cant maintain a lock. It seems to be able to locate me within 12 - 30 feet and then within a mile!!!
Using an application like Endomondo (running, cycling, etc), is completely useless. It can't track my location at all and when it does lock on, it only holds for a few seconds and then gone again.
I took the phone in to Verizon with a complaint about the GPs and screen issues (http://forum.xda-developers.com/showthread.php?t=1239980) and the rep said both were normal for this phone...
Has anyone figured out a way to resolve this problem?

I, too, have the same issue with GPS. I use SportyPal Pro, and cannot use my Droid 3 when running/walking. I can go for a 5 mile run, and SportyPal will show I had ran 6 miles. I can run north to south in a straight line, and when finished, SportyPal will show that I went east and west as much as 400-500 feet off of that straight line and because of that can add anywhere from .1 miles to .5 miles to that 1 mile run.
It is so unreliable that I will use my older decommisioned Droid2 to run with. It works perfectly with the same software.
If anybody has any suggestions, I'm all ears.

bishop0114 said:
I have had continuous issues with the Droid 3. One of my biggest issues is that the GPS seems completely unstable. I have tried turning on/off GPS options, etc...
Weather I try to use Google Maps or another application such as Endomondo, it cant maintain a lock. It seems to be able to locate me within 12 - 30 feet and then within a mile!!!
Using an application like Endomondo (running, cycling, etc), is completely useless. It can't track my location at all and when it does lock on, it only holds for a few seconds and then gone again.
I took the phone in to Verizon with a complaint about the GPs and screen issues (http://forum.xda-developers.com/showthread.php?t=1239980) and the rep said both were normal for this phone...
Has anyone figured out a way to resolve this problem?
Click to expand...
Click to collapse
Sadly, I have the same issues.

Well with only 3 people chiming in, maybe it is bad hardware?

bishop0114 said:
Well with only 3 people chiming in, maybe it is bad hardware?
Click to expand...
Click to collapse
God, I hope not. I have enough problems with this phone as it is.

No problems with GPS for me
Sent from my DROID3 using xda premium

kshen1 said:
No problems with GPS for me
Sent from my DROID3 using xda premium
Click to expand...
Click to collapse
Are you using it for navigation only? Or a similar application for running/walking?
The reason I ask is because I do not notice a problem during navigation. It works great for that without any problems. Until I get to downtown Chicago. I almost expect problems there. Even with my Droid2.

i've only had issues with my gps in areas with lte. when im at college im in a city with lte support and my gps doesn't work (my friend who has an X also has issues with his gps when in areas with lte). when im home where there isnt lte support my gps works fine.

No it's not hardware mine works flawlessly and almost instantly fixes position, tho i have modded the gps.conf found in the etc folder. Details for tweaking this for your region can be found here:
http://forum.xda-developers.com/showpost.php?p=13537801&postcount=1
Many thanx to 75markus for this.
Since we don't have a recovery yet to flash a zip you will need to edit the gps.conf file manually.
Oceanic region can be found in my sig below apart of my camera mod.
-smc

The problem I was having with the GPS from Day 1 is that I would occasionally notice that it would not start up at all when openning a GPS-dependant app (such as Maps or Weatherbug, etc). Whenever that happened, I would have to restart the phone, and then the GPS would be able to initialize again... at least, for a while.
Eventually, I was digging around in the setting and found the "VZW location services" option under "Location & security settings". I unchecked that option and, ever since, I've had no problem with the GPS. It seems that th VZW-based location services were causing the problem. Of course, since then, I've rooted and frozen all of the VZW bloat, so I might be able to turn that option back on with no ill effect. Still, it was as simple enough fix.
My issue might not sound exactly the same as yours, but you could give this a try and see if it helps.
-SR-

I'm not having any GPS issues on my phone. Perhaps it's based on the area your in?
I know it's satellite but.. just a guess.

WarER4X said:
The problem I was having with the GPS from Day 1 is that I would occasionally notice that it would not start up at all when openning a GPS-dependant app (such as Maps or Weatherbug, etc). Whenever that happened, I would have to restart the phone, and then the GPS would be able to initialize again... at least, for a while.
Eventually, I was digging around in the setting and found the "VZW location services" option under "Location & security settings". I unchecked that option and, ever since, I've had no problem with the GPS. It seems that th VZW-based location services were causing the problem. Of course, since then, I've rooted and frozen all of the VZW bloat, so I might be able to turn that option back on with no ill effect. Still, it was as simple enough fix.
My issue might not sound exactly the same as yours, but you could give this a try and see if it helps.
-SR-
Click to expand...
Click to collapse
I have been experiencing the exact same problem and temporary solution (restarting) since day 1, on both my first and second droid 3's. Difference is, I've had VZW location services unchecked since around the time I first got the phones, and I am still experiencing the problem... even as recently as last night. I just double-checked the setting, and indeed, VZW location services is stil unchecked.
Once I have lock I usually have no problem continuously using GPS. Last night, I tracked a two and a half hour walk using the My Tracks app, including a 45 minute stop for dinner indoors. For the first 10 minutes, it couldnt find a signal, so I restarted. It got a lock almost instantly following the restart and never lost it after that. I had the app running for the whole excursion. As expected, it got a little confused while I was inside, but automatically picked the signal right back up when I got back outside and tracked my entire walk back home.

a_lazy_dude said:
I have been experiencing the exact same problem and temporary solution (restarting) since day 1, on both my first and second droid 3's. Difference is, I've had VZW location services unchecked since around the time I first got the phones, and I am still experiencing the problem... even as recently as last night. I just double-checked the setting, and indeed, VZW location services is stil unchecked.
Once I have lock I usually have no problem continuously using GPS. Last night, I tracked a two and a half hour walk using the My Tracks app, including a 45 minute stop for dinner indoors. For the first 10 minutes, it couldnt find a signal, so I restarted. It got a lock almost instantly following the restart and never lost it after that. I had the app running for the whole excursion. As expected, it got a little confused while I was inside, but automatically picked the signal right back up when I got back outside and tracked my entire walk back home.
Click to expand...
Click to collapse
When you look at your walk on the map, is it true to where you actually walked? If I do that same walk on my phone, it will show me deviating off course as much as a 1/2 block and then back. I can tolerate that deviation once and maybe twice during my runs/walks. However, mine does it the majority of the time, adding bogus mileage to my walks/runs. In an hour's time, it will deviate approximately 20-30 times.

eallison978 said:
When you look at your walk on the map, is it true to where you actually walked? If I do that same walk on my phone, it will show me deviating off course as much as a 1/2 block and then back. I can tolerate that deviation once and maybe twice during my runs/walks. However, mine does it the majority of the time, adding bogus mileage to my walks/runs. In an hour's time, it will deviate approximately 20-30 times.
Click to expand...
Click to collapse
Just took a closer look at the track it recorded. I definitely do see these kinds of deviations, but they seem to only be in areas where I think it'd be reasonable to expect them. I live in a suburb, so I don't have any tall building to mess with the GPS reception, instead, I have somewhat steep hillsides. It seems I get a fair amount of deviation in the (significantly) hilly areas (it looks like I was walking down people's driveways, then across their front yards, when in reality I was just walking more or less straight down the sidewalk), but in the flat areas the line has almost no significant deviations, just some minor noise. Next time, at the risk of my fiance calling me a geek, I'll take my Droid 1 along for the trip, and see how the two records compare.

a_lazy_dude said:
Just took a closer look at the track it recorded. I definitely do see these kinds of deviations, but they seem to only be in areas where I think it'd be reasonable to expect them. I live in a suburb, so I don't have any tall building to mess with the GPS reception, instead, I have somewhat steep hillsides. It seems I get a fair amount of deviation in the (significantly) hilly areas (it looks like I was walking down people's driveways, then across their front yards, when in reality I was just walking more or less straight down the sidewalk), but in the flat areas the line has almost no significant deviations, just some minor noise. Next time, at the risk of my fiance calling me a geek, I'll take my Droid 1 along for the trip, and see how the two records compare.
Click to expand...
Click to collapse
I've attached screenshots from two runs. D2 is this morning's run with my Droid 2. It's flawless. D3 is the last run I did with my Droid 3. Looking at it you can understand my disgust with it. Ignore the big missing section from both shots. I wouldn't want anyone knowing the exact location of where I live. Someone might come steal my Droid 3.

eallison978 said:
I've attached screenshots from two runs. D2 is this morning's run with my Droid 2. It's flawless. D3 is the last run I did with my Droid 3. Looking at it you can understand my disgust with it. Ignore the big missing section from both shots. I wouldn't want anyone knowing the exact location of where I live. Someone might come steal my Droid 3.
Click to expand...
Click to collapse
WOW... That is awful but a great example of the concern with this phone. You are actually doing much better than me. Mine is only able to triangulate down to about 20 feet and then it bounces between 20 and 300 feet!!!
I am going to call VZW today and see about a replacement phone but I doubt it will resolve the problem.

I just called VZW and once again, they said the accuracy was normal... They said none of their phones can lock on with the accuracy I described and if it has, I have been lucky. He said their phones are only accurate within 500 feet!
I explained to him that with that accuracy, it would be totally useless to use as a navigation device...
He looked through their documentation and said he has no record of other people having issues with the GPS... He also said he has no record of the blue tint when taking pictures.....
Oh well. I hope the replacement fixes it...

bishop0114 said:
WOW... That is awful but a great example of the concern with this phone. You are actually doing much better than me. Mine is only able to triangulate down to about 20 feet and then it bounces between 20 and 300 feet!!!
I am going to call VZW today and see about a replacement phone but I doubt it will resolve the problem.
Click to expand...
Click to collapse
With that kind of change in accuracy, it seems like it isn't using the GPS as all, but just the cell towers. Is the GPS logo showing in the notification bar when that is happening? If it's there, is it blinking or solid?
-SR-

bishop0114 said:
I just called VZW and once again, they said the accuracy was normal... They said none of their phones can lock on with the accuracy I described and if it has, I have been lucky. He said their phones are only accurate within 500 feet!
I explained to him that with that accuracy, it would be totally useless to use as a navigation device...
He looked through their documentation and said he has no record of other people having issues with the GPS... He also said he has no record of the blue tint when taking pictures.....
Oh well. I hope the replacement fixes it...
Click to expand...
Click to collapse
My humble opinion of VZW representatives...they're all full of BS. They're going to tell you what they need to tell you to get your out of the store or off of the phone if you're not buying anything. A representative's main concern is sales. Sell him another phone, renew his contract, add a line, add a feature.
This issue may be better addressed to Motorola directly. I may make that phone call today.

I just got off the phone with Motorola tech support. Same story as VZW gives. There are NO known issues with the Droid 3. I asked about the GPS, the bluish pics the cam takes and battery life. The only thing the tech would say is the phone "needs to be evaluated"

[Q] Can you improve Note's GPS accuracy?

I am quite annoyed because whenever I run with my Note the tracking is average to bad. Even under clear sky on a 400m track with no tall buildings around I keep getting errors - most annoying is speed variation.
E.g. today I did 14 tracks (5.6km) at about 5-5.30 mins/lap with 1-2 minute break in total. My speed was constant and average speed is correct but GPS shows high variations.
Is there any way to improve accuracy so I can adjust my speed when necessary? Below is a screenshot from Google Earth after importing my track. I always ran on the first lane. Not across the grass, jumping fences or changing lanes All 14 laps on the first (smallest, 400m lane) which you can see has a white visible contour.

Under your settings-location do you have sensor aiding checked? I think it's generally better not to. You could also try using a different app for tracking the workout. Different apps can poll the gps at different intervals. Finally, not that it's helpful, but my guess would be that running around a track is probably the hardest test for gps because you're constantly changing direction. Have you had better luck with other devices?

mihaig said:
I am quite annoyed because whenever I run with my Note the tracking is average to bad. Even under clear sky on a 400m track with no tall buildings around I keep getting errors - most annoying is speed variation.
E.g. today I did 14 tracks (5.6km) at about 5-5.30 mins/lap with 1-2 minute break in total. My speed was constant and average speed is correct but GPS shows high variations.
Is there any way to improve accuracy so I can adjust my speed when necessary? Below is a screenshot from Google Earth after importing my track. I always ran on the first lane. Not across the grass, jumping fences or changing lanes All 14 laps on the first (smallest, 400m lane) which you can see has a white visible contour.
Click to expand...
Click to collapse
If you are rooted
get 'Faster Fix' from market
select your region from dropdown and - Go
it requires one time only

pezx44 said:
Under your settings-location do you have sensor aiding checked? I think it's generally better not to. You could also try using a different app for tracking the workout. Different apps can poll the gps at different intervals. Finally, not that it's helpful, but my guess would be that running around a track is probably the hardest test for gps because you're constantly changing direction. Have you had better luck with other devices?
Click to expand...
Click to collapse
Yes, I have that option checked because it is supposed to improve accuracy. I will disable and see if that helps.
I use Endomondo and Cardio Trainer and both have the same issue at the highest frequency of gps polling - 1 sec. It's not an app fault because I downloaded the points into GEarth and you can see this is the date they get. I agree they could use better filtering but this is another topic.

It has one of the best GPS chips in existence with GLONASS and a Barometer. Don't think you can make it "better." It's as good as a phone GPS gets.

ericshmerick said:
It has one of the best GPS chips in existence with GLONASS and a Barometer. Don't think you can make it "better." It's as good as a phone GPS gets.
Click to expand...
Click to collapse
I agree to that brother....
For a small built in GPS reciever it works quite well.....
Sent from my GT-N7000 using XDA App

I think, from experience with other phones, that the other sensors will smooth things by assuming you're still moving in a certain direction and can mess things up when turning (which is pretty much your entire run). I personally have never had luck with any sort of gps on a track. I just don't think anything outside of military gps has accuracy fine enough to handle it. If you find otherwise, I'd love to hear about it though.