iPhone 8 GPS problems

When you say you have been using GPS, do you mean you verified with GPS Diagnostic at several intervals during your walk that you had a GPS signal? If not, the GPS connection might have cut out at various points during your walk, resulting in the divergence on your map.

Have you tried factory resetting, and then testing GPS on Apple Maps before restoring your backup?

Yes, I have done all that.

Gps signal is still there but it drops most of the satellites. It usually gets a decent signal from only three satellites whereas my Polar sportwatch and dedicated Garmin gps get over ten satellites. The problem with my iPhone 8 is that it is not able to maintain the connection to the satellites. When I first open a map app it gets an accurate location which lasts for a minute or so. But after that it always loses most of the satellites and the signal becomes poor. Same happens if I close the app and start it again. Good gps fix for a brief moment and then it drops again.

Factory resetting didn’t help either. Apple maps app have just as bad results right after resetting as before.

And by the way, this is now my third iPhone 8 that has exactly the same issue.

You've replaced your iPhone 8 twice?!

When you say it loses most of the satellites, how many does it lose?

(I think you only need 3 for the GPS function to work.)

And what level of accuracy are we talking about?

Are you happy with 16meters, what are you aiming for?

If you did that SIM trick (noting the disclaimer) properly, and it didn't work,

and you did factory reset, and tested without restoring, and that didn't work,

the only other things I can think of are:

*update to latest iOS11.4.1,

*make sure Compass has True North on and is calibrated propertly

https://www.getdroidtips.com/proper-compass-calibration-iphone-x/

*turn all apps in Location Settings to Never, except the GPS apps you really need

*use only one GPS app at a time, and turn off all other apps (just to be safe)

Does your mobile carrier use its own network of base stations or is it a MVNO/MOLO that leases the infrastructure from other carriers? https://en.wikipedia.org/wiki/Mobile_virtual_network_operator

Customers of MVNO-type carriers can have problems with their phones taking too long to give them an Assisted-GPS-based location and/or losing it. I think this mainly affects non-Apple phones, but it might be relevant.

Also, if your issue is limited to one neighborhood, the problem could be Pokemon GPS jammers or GPS spoofing

These are just shots in the dark... running out of ideas...

Yes, twice. My phone is offered by the company I work for and we have quite good customer service for phones.

About gps satellites. To get a fix three satellites is bare minimum and then the accuracy won’t be very good. Four satellites is the minimum for three dimensional positioning. The more satellites the better accuracy.

The app GPS Diagnostic sadly doesn’t specify how many satellites it is connected to. >4 has only one bar in the diagram. In my case that bar is usually very low or even 0 %. Also the first three satellites have many times low signal qualities.

The accuracy for modern phones with gps and glonass chips should be well under 10 m. I don’t consider 16 m accurate at all. I am a geocacher and 16 m accuracy makes finding caches very difficult. On open terrain the accuracy should be more like 6 m (which my previous iPhone 6s was able to get). For comparison my dedicated Garmin gps is able to obtain 3 m accuracy.

Then the other matters:

- SIM trick didn’t do anything.

- Compass should have nothing to do with getting an accurate location. It is only for getting a heading. Anyways, it is calibrated.

- I have iOS 11.4.1. It doesn’t help.

- Turning off location services for all other apps cannot be the solution. I need location services on multiple apps.

- This issue isn’t limited only to my neighbourhood. I experience it everywhere anytime.

- My carrier has its own network of base stations.

I am pretty sure this is a software bug that Apple needs to fix asap. Sadly it seems that Apple hasn’t even confirmed this bug.

Ah, I think we may be talking cross-purposes.

My issue was that I had no GPS signal at all. You obviously need greater accuracy than I do.

Before the SIM trick, I had zero GPS signal according to the GPS Diagnostic app. The SIM trick restored the A-GPS function on my iPhone X, giving me 10-20m accuracy according to that app (about the same as your 16m mentioned above). However, for comparison, I just tested on my wife's 6S. She gets the optimal plus/minus 10m reading on it! I think my iPhone X has been slower to get the initial position lock, and less accurate, than my old iPhone 6 and my wife's iPhone 6S from the very beginning.

I also noticed that the Altimeter reading in the Barometer app is less accurate than on hers. I think this also affects the three dimensional positioning you referred to:

"Barometer: You might think of a barometer, which measures air pressure, as primarily a weather-prediction device, but it's not used for that purpose on an iPhone. The barometer supplements the GPS chip for measuring elevation changes to create more accurate elevation and elevation-change readings."

https://www.lifewire.com/iphone-gps-set-up-1683393

PS: I agree the Compass function is probably irrelevant in your case, but some sites recommend it, so just to rule it out, I would double-check your Compass is set with True North on, i.e. not Magnetic North (Settings, Compass, True North) and your Compass Calibration is turned on (Settings, Privacy, Locations Services, System Services, Compass Calibration)

Ah, okay. The first post on this thread sounded just like my problem so I just replied to the last writer (you) on the thread.

My accuracy is 20-50 m which is not tolerable at all in my opinion.

I have checked the compass setting and they are fine.

I am starting to get really frustrated with this problem. :( Customer service said that the next step might be contacting Apple about the problem. I’m not very optimistic..

Sorry to hear that. You didn't mention your barometer. You could also check that too, although I doubt it would improve your planar accuracy.

Does the GPS Diagnostic app give you a reading of 50m while showing orange or green GPS bars? That is barely better than the reading of 65m the app gives me when turning off GPS and relying purely on Wifi and Cellular networks.

If it is regularly 50m, I would guess something is broken, rather than just inferior performance relative to old models.

There have been other fixes relating to vehicles and Bluetooth systems in this thread, but I think you are having problems just walking/jogging with your phone.

Another possibility is your company supplied you with three phones from the same faulty batch of iPhone 8 models, but that is unlikely.

Grasping at straws here.

If you can't get consistent readings below 20m, don't bother with Apple Tech phone service, go into the store and demand ask patiently for answers. Sigh... I feel your pain... this is total self-service... the blind leading the blind...

I'm on my second iPhone 8 plus. Had a whole history with apple support, they identified it as an hardware failure, but when the new phone also gave issues with accuracy, they had to do some more research.

When I finally contacted them for a status update, they said the behavior was within the parameters for the iPhone 8 plus. The support guy literally told me: "The GPS for the iPhone 5C and 6S (my reference models) are more stable and accurate than the iPhone 8+."

It seems they will not recognize the issues with the GPS for iPhone 8/8+ and iPhone X. And I don't understand why not more people are complaining and why no tech site has written anything about it. iOS 12 is around the corner, 11.2.5 was supposed to fix it, we're on 11.4.1 and they will just not help their users. I think nobody is using their GPS enough to notice the awful accuracy and constant drift.

the.JoOLz,

What level of accuracy are we talking about? Many of us here downloaded GPS Diagnostic which costs almost nothing from the App Store. Since "fixing" my iPhone X, I now get readings of between 10-20m fairly consistently. I am curious what their parameters are.

the.Jo0Lz wrote:

It seems they will not recognize the issues with the GPS for iPhone 8/8+ and iPhone X. And I don't understand why not more people are complaining and why no tech site has written anything about it. iOS 12 is around the corner, 11.2.5 was supposed to fix it, we're on 11.4.1 and they will just not help their users. I think nobody is using their GPS enough to notice the awful accuracy and constant drift.

I have had no issues to complain of with the GPS in my iPhone X; I use it daily for Waze and it gets me where I want to go and with Wi-Fi on it's as accurate as any other iOS device I've used.

As an aside, a little about accuracy:

US Government Info: GPS Accuracy

Thanks William. Sounds like you have no problems. We don't hear from people without problems because this tends to be a self-selecting group of people looking for fixes for broken GPS functions.

That link says smartphones have a typical accuracy of 4.9 meters in an open sky, but that is not necessarily the parameters the Apple staff are using, considering the issues Joolz was suffering. The link also says it depends on the "receiver design features/quality".

Correct; Apple does not publish specs regarding its GPS accuracy, and Location Services always operate in conjunction with other methods such as using the published locations of various WiFi hotspots.

Note that as Apple publishes no specs for GPS accuracy and the app is a third party product, what it has to say actually means little, especially as the 4.9m figure is for a "typical smartphone" and was based upon user-provided survey data, not actual data taken from phones.

PS:

What Joolz was told by the staff, i.e. that "The GPS for the iPhone 5C and 6S (my reference models) are more stable and accurate than the iPhone 8+.", syncs with my own experience with the iPhone X:

Comparing an iPhone 6S with an iPhone X side by side, in the same location, using the same mobile carrier, and the same most recent iOS, and the same GPS Diagnostic app, I get a quicker lock-on and better accuracy for the iPhone 6S than for the iPhone X.

Have you checked your gps accuracy with anything else than Waze? When navigating on Waze it locks your position to the road. I also can navigate with Apple maps. It just may be a couple of ten meters behind.

The problem really comes into life when I use an app that shows your real location (not locked to road). For example, it’s impossible to track my sports activity with my phone. 20-50 m accuracy just isn’t enough. Even when walking a straight line in open terrain results a route that is nothing close to a straight line.