GPS is incredibly inaccurate on 3GS..

[duelingdragons]

Maps is telling me that I'm about 2 miles away from my actual location. I've tried in a few different places.

Anyone else having this problem? :(

[vilasgn]

Wow...if this is really a common issue then I am really disappointed. This means Tomtom software cannot be used with in-built GPS chip.

Good job Apple if this true!

BUT, when I read engadget 3G S review, it specifically mentioned that the iPhone 3GS GPS is very accurate.

Strange!

[geoffreak]

Try restarting your iPhone. It is normally very accurate.

[iPhone guru]

I just got my 3GS and it seems to be the same regarding GPS as the 3G. Not much testing yet but I did a short ride with my bike already and it seemed fine. I'm using the app B.iCycle with a bike mount. Never had a GPS problem with the 3G and the 3GS seems to be fine as well. Would suck if the 3GS has worse or cheaper GPS than the 3G. Anyone else having issues???

[xxMACxx]

Mine seems very accurate, and much faster lock on than my 3G.

[adamdodson]

Yeah, try restarting. Mine locked my location immediately.

[duelingdragons]

Try restarting your iPhone. It is normally very accurate.

Tried, its better (closer) now, but still way off.

[Kepesk]

I found an area in a nearby town where my phone thinks I'm in the Netherlands. Consistently. Whenever I'm in the south half of the town, my phone thinks I'm in the Netherlands. Weird.

[Axxl]

Pinpoints my position exactly...
Alex

[CocoaPuffs]

Tried, its better (closer) now, but still way off.
Where are you exactly? Under wide open space?

[Rodimus Prime]

Well it depends how your locations is being figured. If it is using the sats it is fairly good but the iPhone could easily be using triangulating you position based on 3 or more sell tower. The problem with the tower method is it is not as accurate and it could be your phone is having trouble being picked up by the 3rd tower.

[duelingdragons]

Where are you exactly? Under wide open space?

Yep. Out in my yard... no trees, etc.

[Resist]

Pinpoints my position exactlyThis is not possible, since the accuracy to GPS for the general public is limited. Only the military gets pinpoint accuracy.

[slpdLoad]

At both work and home, it places me within a few meters of my location. Sometimes it gets within about 20 meters and then updates to my exact location a couple seconds later.

Obviously it's only as "exact" as civilian GPS can be. :rollseyes:

I couldn't be happier with it.

[notjustgc]

Mine was as perfect as it could possibly be, and definitely faster than the 3G at getting a lock (even indoors, albeit near a window). Also, my compass has been pretty much spot-on since I did the "figure eight" calibration moves.

[MattZani]

Im Definitely stood with in the Dot on mine :P

[DiveN4Gold]

This is not possible, since the accuracy to GPS for the general public is limited. Only the military gets pinpoint accuracy.

Depends on what you consider "pinpoint" accuracy - consumer GPS can be pinpointed within around 10 feet. So I'd call that pretty "pinpoint". I'm not sure what knowledge you think you have about military GPS, but I've been in several military HUMVEE's and they're certainly not much more accurate than that.

[Hutch1]

This is not possible, since the accuracy to GPS for the general public is limited. Only the military gets pinpoint accuracy.

That is not true, it was called selective availability which introduced variable errors in the signals which degraded civilian (non-military) receivers, but that was turned off in 2000. Military and Civilian GPS system are basically the same now.

[Resist]

Military and Civilian GPS system are basically the same now.You are correct, but I still think the military gets slightly better accuracy on their GPS devices. While we get accuracy within 10's of feet, I am sure they get it within inches.

[Resist]

Depends on what you consider "pinpoint" accuracyDidn't know there were different definitions for the word "pinpoint".

If you were to take a pin and stick it on a map, the point is where you are. This is an exact location, not an area within a circle of accuracy.

[pooryou]

I found an area in a nearby town where my phone thinks I'm in the Netherlands. Consistently. Whenever I'm in the south half of the town, my phone thinks I'm in the Netherlands. Weird.

Every town should have a place like that :cool:

[dagomike]

Mine is very accurate.

[Vid]

Didn't know there were different definitions for the word "pinpoint".

If you were to take a pin and stick it on a map, the point is where you are. This is an exact location, not an area within a circle of accuracy.

Depending on the diameter of the pin and the scale of the map that is most definitely a circle of accuracy.

[Michael CM1]

It told me I was in the middle of my cul-de-sac, not my bedroom. So it's off by maybe 50 yards.

[gloss]

Mine's spot on. Within. Couple of yards, at least.

[The General]

Is there a big blue circle around your blue dot?

Does it look like this:
http://img37.imageshack.us/img37/2620/img0033.png

Or does it look like this:
http://img37.imageshack.us/img37/6357/img0034.png

The first one is just cell tower triangulation. If you have GPS, it will be very accurate and it will be just a blue dot or a blue dot with a small circle around it.

The blue circle is the level of accuracy. If your phone is telling you that you're 2 miles from where you are and is just a blue dot with no circle, then something is wrong with your phone.

[ALittleDrive]

Every town should have a place like that :cool:

Maybe you should go to the Netherlands......seriously, its nice!:)

[lilmitchmitch]

When in my house, the GPS is flawless. Today while I was out at dinner it said that I was near St. Louis -- about two hours from where I'm at. I'm not sure why it was like that because I never ran into this problem on my 3G... oh well, hopefully when I actually need to use it, it'll cooperate. :rolleyes:

[PhxBlue]

GPS is spot on for me.

[E3BK]

Mine locks much faster is is def more accurate than the 3G.

[AET10]

Mine is so accurate it can track when I walk around my house from room to room and down the hall...no joke. On satellite view I can walk around my backyard and it tracks step for step. Crazy accurate...

[Synthetickiller]

GPS is spot on for me.

Ditto, 10 feet off max. Dead on accurate for me.

[Jamz00]

I got lost using the new maps tonight. The flipped map confused the hell out of me and I ended up in a very different place than I intended to go. It was scary.

[Canuckk]

Maps is telling me that I'm about 2 miles away from my actual location. I've tried in a few different places.

Anyone else having this problem? :(

Your problem is most likely not related to the phone itself, but to the network. Sometimes, (and this is what I understand of it, I could be off though) the cell tower codes telling the phone their position get mixed up, causing the phone to believe you are at an entirely different location then where you really are. This problem happens on the iPhone 3G as well, though it was more common on the earlier, 2.0.x firmware (it happened to me all the time and was really frustrating). Try moving a few blocks away from your current or testing position then try again, it should then correct itself. If not, then it could be some other problem that I'm not aware of.

[Jamz00]

is anyone using a turn by turn app yet? what's a good one if they exist yet?

[ericvmazzone]

This is not possible, since the accuracy to GPS for the general public is limited. Only the military gets pinpoint accuracy.

That changed a few years ago. The Civie models are not accurate to the same degree as the mil spec systems.

[skwoytek]

Your problem is most likely not related to the phone itself, but to the network. Sometimes, (and this is what I understand of it, I could be off though) the cell tower codes telling the phone their position get mixed up, causing the phone to believe you are at an entirely different location then where you really are. This problem happens on the iPhone 3G as well, though it was more common on the earlier, 2.0.x firmware (it happened to me all the time and was really frustrating). Try moving a few blocks away from your current or testing position then try again, it should then correct itself. If not, then it could be some other problem that I'm not aware of.

The "A" in AGPS only helps the device determine initial location for satellite acquisition. In the old days you had to actually tell a GPS what region you were in before it could get a good location lock, even then it still took several minutes before the GPS would show an exact location.

The cell towers are the "A" in AGPS. They only narrow down your location, after that it's all satellite.



Also, having used PLGRs extensively in Iraq, I can tell you they're no more accurate than civilian GPS these days.

[dialed1]

Try putting the phone on edge instead of 3g that works for me but probly same as restarting.

[Senn]

mine was totally wrong on an hour long driving trip

and the compass is horrible while driving as well

[sommls]

From my own n=1 experience:

1) 3G gps has not been documented anywhere I've read to be different from 3GS gps.

2) my 3G is less accurate than a dedicated, older model gps (Magellan Meridian Gold). I can walk through my house with the Meridian and accurately see position changes within 5-10 feet. iPhone gps gets me within the right building (about 50 foot resolution).

3) in other places (my car), direct comparison of the two yields pretty much the same difference. No, the passenger's looking at them, not me...

[itsmequinn]

I'm actually having a problem with an iPhone 3g where only thecell tower triangulation will work, not the actual gps. The reading is about as accurate as the triangulation method usually is, but the halo around the blue dot never zooms in and the blue dot never starts updating live like the gps always used to. I have tried reseting and reseting my network settings but nothing works. This is since upgrading to 3.0.

[Bentov]

I posted this yesterday, but i can't seem to find my post. change it from true north to magnetic north, then the gps and maps will be dead on.

[ubercool]

Maybe you should go to the Netherlands......seriously, its nice! :)

I agree, very nice, or "zeer mooi" as they would say there. :D :cool:

[woodtrain54]

I posted this yesterday, but i can't seem to find my post. change it from true north to magnetic north, then the gps and maps will be dead on.

Nevermind, I didn't even see the info button in the compass app

[Chupa Chupa]

I wouldn't say it's inaccurate as much as its inconsistent. There are times it will pinpoint me dead on, and other times when it's a half mile off. And other times when it has me at the right coordinates, but wrong street.

[Excellerator]

I'm actually having a problem with an iPhone 3g where only thecell tower triangulation will work, not the actual gps. The reading is about as accurate as the triangulation method usually is, but the halo around the blue dot never zooms in and the blue dot never starts updating live like the gps always used to. I have tried reseting and reseting my network settings but nothing works. This is since upgrading to 3.0.

My 3G is doing the same thing since upgrading to 3.0. Must be a bug. I have tried resetting and it doesn't fix it.

Update: The bug seems to be in the Maps app because when I ran MotionX GPS it worked fine, then I went back to the Maps app it then worked. Weird. Almost like the Maps app isn't turning it on.

[iPhone guru]

My 3G is doing the same thing since upgrading to 3.0. Must be a bug. I have tried resetting and it doesn't fix it.

Update: The bug seems to be in the Maps app because when I ran MotionX GPS it worked fine, then I went back to the Maps app it then worked. Weird. Almost like the Maps app isn't turning it on.

Same here. I have the same problem with the maps app but my cyclometer app B.iCycle works very well on the 3GS with OS 3.0! It shows very accurate position in the map while I'm biking and the calorie and altitude calculation seem to be quite good as well. So it must be a problem of the maps app.

[itsmequinn]

I tried motionx gps lite but after about two prompts to "continue searching for satellites?" it still was stuck on triangulation. Any one else still have the problem?

[iPhone guru]

I tried motionx gps lite but after about two prompts to "continue searching for satellites?" it still was stuck on triangulation. Any one else still have the problem?

B.iCycle took about 30s to find GPS and the map showed my position exactly in my backyard. I guess about 5m off but thats very cool for GPS.

[Rootus]

Mine's spot on. Within. Couple of yards, at least. Mine too. Hell, it put the pin on the correct room of the house I was in ...

[rburly]

Mine is spot on!

[Chalkman]

I've been a longtime macrumors reader but I just noticed something regarding the gps. I, too, was having a very inaccurate reading when using Maps as well as MotionX pro (which I bought just to see if it would 'fix' the problem). Well, I kept getting the same issue (about 1/2 mile off). Ironically when I switched to wifi (off of 3G), I tried Maps again: It showed the original blue dot (off 1/2 mile) and then repositioned to my 'exact' location (very accurate). I think the problem is the 3G connection that is throwing off my position. Even the MotionX program repositioned to the exact position. I then took off wifi and went back to 3G and the results.... back to the wrong position! Same with MotionX.

So the problem (at least with me) is the 3G connection. I just tested my wife's iphone (the no GPS 1st gen. which only does triangulation; of course she got my old phone :) ), and with Maps our positioning location was WAAAAY off (not even close!), but I know that accuracy was been better in the past on this phone. I duplicated the results so I know it wasn't a fluke.

Of course, we've had extremely stormy weather on the east coast so maybe that has something to do with it?

btw, I live near NYC and we have a very strong 3G network here (at least it seems it).

Long story short: if you have a wifi connection, try that over 3G and see if that makes a difference. It did for me!

[itsmequinn]

Is it possible that it's the 3gs launch that is throwing this off? I remember that gps accuracy was a problem with the original 3g right around launch. I just assumed that it was a software update that eventually fixed this but maybe it was that AT&T eventually beefed up the network a little or the hype died down. Just a theory, since the speed of the gps lock is largely dependent on the cell network location since it's agps.

[DiamondMac]

I have found it to be quite accurate but there are always exceptions for some reason

There are a few spots near me where the GPS can't find me though it is only a few times in the last year

[TuffLuffJimmy]

turn off location services. Then turn the phone off, boot, then turn location services back on.

[itsmequinn]

turn off location services. Then turn the phone off, boot, then turn location services back on.

Still refuses to use the actual gps receiver... Thanks though

[vansouza]

Maps is telling me that I'm about 2 miles away from my actual location. I've tried in a few different places.

Anyone else having this problem? :(

I am having the exact opposite experience; my 3G S finally gets not only my street correct but nails the exact address.

[bossxii]

You are correct, but I still think the military gets slightly better accuracy on their GPS devices. While we get accuracy within 10's of feet, I am sure they get it within inches.

Military does not track within inches, are you tossing a dart at some answer chart on a wall? Clearly you haven't researched the topic at all and are totally unaware of how GPS work (Both Civilian and Military).

I think this is one of the better answers found on the topic, question being do civilian and military use the same GPS satelites?

"The answer is yes. The GPS is a constellation (group of satellites), 24 overall, that are in 12-hour orbits about the earth. They are synchronised so that it's possible to get signals from up to 12 of them. Four are needed to get one's location, but more signals means greater accuracy.

Up until May 2000, there were the civilian signals and the military signals. Basically, the military signals required special components to be received, thus it was limited. The civilian signals were not as precise, usually allowing for about a 30 metre (100 feet) accuracy.

During the Clinton Administration, they decided that the civilian application of GPS outweighed the risks involved with precise signals, so on 1 May 2000 the select availability was dropped, and with a small update, civilian GPS receivers could utilise the military signals, giving an accuracy of roughly 3 metres (10 feet)."

[PNutts]

Obviously it's only as "exact" as civilian GPS can be.

Actually, the civilian signal is no longer degraded and now has the same accuracy as the military.

[slpdLoad]

Actually, the civilian signal is no longer degraded and now has the same accuracy as the military.

Thanks for the correction, good to know. I haven't kept up with that stuff.

[skwoytek]

Up until May 2000, there were the civilian signals and the military signals. Basically, the military signals required special components to be received, thus it was limited.

Having been in the military until 2006, I can tell you this is not completely accurate. We had to get encryption keys loaded on our PLGRs before use.

There is a specific encrypted military signal from each satellite to ensure that the GPS signal is authentic and that requires special components. But, no - it doesn't affect accuracy.

[Jeremy81]

No, it displays the blue dot literally right over my house. It's very accurate in my case.

[woodtrain54]

If our gps is a few miles off, do you guys think this is something worth calling apple or bringing to an apple store over? or should we wait for a little while to see if its just because of the release.

[scotland007]

I am having the exact opposite experience; my 3G S finally gets not only my street correct but nails the exact address.

Mine too, bang on shows my home address.

[Diode]

Remember google maps might be off and not the GPS.

Testing with google maps is NOT a good way to test accuracy.

[grantsdale]

If you were to take a pin and stick it on a map, the point is where you are. This is an exact location, not an area within a circle of accuracy.

Yes, but how big is the map? If the map is of the world, that pin could very well cover your entire state.

[Chalkman]

Remember google maps might be off and not the GPS.

Testing with google maps is NOT a good way to test accuracy.

I'm still not sure about google maps. As I said above, when disabling 3G and using wifi the positioning blue dot maneuvers to a more accurate position. The map may be off, but I'm definitely getting a more incorrect position when either 3G or EDGE is activated. Hopefully once a turn-by-turn app is available there can be a calibration tool (using the app/GPS to determine position, then dragging the blue pin to a precise location and calibrate the map to the adjusted position. Could be possible...

I know that at this point relying on the GPS for turn-by-turn couldn't (at least where I live) accurate enough to be useful.

[citron230]

Mine seems very accurate. It also locks onto the sat much faster. I also love the feature to point the map in the direction traveled.

Good job Apple!!

[Cjr605]

If I turn my GPS on my iPhone 3G S it will generally say I am driving through grass on the side of the road. Or, if I am sitting still in my house, it says I am in my neighbor's house. Also, if I turn on a road the dot continues moving straight through the intersection to where I am not, and 5 seconds later pops up where I actually turned.

Is this normal or do I need to get it fixed?

[daneoni]

Mine is pin point accurate as is the compass...it even found me despite being in my flat on the 2nd floor which my 3G could never do

[phillipjfry]

Remember google maps might be off and not the GPS.

Testing with google maps is NOT a good way to test accuracy.

I have to second this. Google, for some reason or another, does NOT have Avon, IN mapped out too well. Tried to find a dunkin donuts in Avon one time, it had it damn near to Danville (way west of Avon). Several other locations in Avon were off by several miles (again close to Danville). :confused:

[firewood]

Sometimes the blue dot wanders off across the street and down a few houses from where I'm standing with my iPhone.

Sometimes the blue dot is so bloody accurate that I can walk around my car parked in my driveway, and the blue dot will follow me around the car's overhead image as it shows in Google maps (assuming I parked it the same spot).

Must be the luck of what or how many satellites are currently in view overhead or something.

[Leehanvoon]

Maps is telling me that I'm about 2 miles away from my actual location. I've tried in a few different places.

Anyone else having this problem? :(

Yea..
I'm havin this problem too..
Tried in middle of the road at the back of my house
resetting the phone got it accurate for once
but it got inaccurate again
(tried turnin on & off airplane mode)
then maps again

I have pin my house exact location on map
when I'm getting direction to my house from the current location (which was the open road back of my house)

it shows I'm 500m off..
I guess it showed location based on the cell tower or something

my garmin 255w display an accurate gps loc

[old-wiz]

It told me I was in the middle of my cul-de-sac, not my bedroom. So it's off by maybe 50 yards.

gps doesn't get good signals inside of buildings.

[shotts56]

Correct. Very few satnav units work indoors, even standalone units.

[quilita]

I have had the 3g and the 3gs when I first got the 3g the gps worked fine then one day it didn't. I got the 3gs and have problems with it even more. I never gets my location right so Ill be completely lost. It will tell me to turn at streets no where near idk why it does this but im in a new city and need it to work.