iPhone X GPS defects
After thoroughly investigating, including running multiple tracking apps on both my iPhone X and some older devices I have, and researching other people’s findings on the internet, it has become clear to me that the Intel XMM7480 modem (which also contains the GPS) contained in the A1901 variant of the iPhone X is significantly inferior to the Qualcomm Snapdragon X16.
For those folks who only ever use their phone for driving directions or other things where you really only need instantaneous position and being off by 20 or 30 meters isn’t an issue, maybe you wouldn’t notice. But as an avid runner and user of fitness trackers this problem is a complete showstopper. Every other device I have seems to have no trouble getting a GPS fix that is accurate to about 2.5 to 5 meters (depending on conditions), but even on a sunny clear day with no objects obstructing the sky the best my iPhone X can seem to manage is 10 to 16 meters accuracy. As a result, when I go for a run it winds up cutting corners, meandering all over, and recording inaccurate distances even for short trips.
Obviously, I do not expect the same precision that expensive survey equipment and military equipment can get (less than a meter… or even a centimeter in some cases) using the more accurate encrypted satellite signals which are restricted for civilians. If I was running an entire 26.2 mile marathon and it ends up off by a quarter mile, I chalk it up to either not running perfect lines (especially since many large marathons are on wide streets and can be crowded so you often end up in a sub optimal path if you aren’t up front where the crowd is thin) through the turns or just the fact that GPS in consumer devices isn’t totally perfect — likely a combination of both.
Unfortunately, with this phone it is different. It is not uncommon to go for a 3 mile run and have it be off by over a quarter mile when I get done. That is not a small amount thats an entire lap around a track which is a lot to be off by in such a short time. It is unusable, and the longer you go the more it is off by… it is hard to predict exactly how bad it will be without actually trying a particular course, but it is likely that running 8 or 10 miles will result in the GPS distance being off by nearly a mile. Its unacceptable and unusable. It cannot be relied upon if you want to follow a training plan or even to simply know what your pace was on your run!
Apple denies that there is a problem, but they’ve released multiple iOS updates with “GPS fixes” and they are still trying with iOS 12 betas… clearly they know there is a problem, but I don’t think this is something that can be fixed with software. You can “smooth” out bad data by supplementing with other sensors to filter or “fuse” data but if the GPS chip supplying data is inaccurate its still going to be suffering.
Had I known that the GPS in the Intel chip is defective, I would have never purchased my iPhone X at an AT&T store, I would have gone to an Apple Store to purchase an “unlocked” A1865 version and then just activated it on AT&T. Instead I’m stuck dealing with Apple Support who are being very unhelpful, so far they have sent me a second iPhone X A1901 unit and its GPS is performing exactly the same as the first one. If this were really a “new” and “unknown” issue as they claim, I could understand more that they might want to try the same model first to rule out that it was just a single defective chip, but when I see dozens of online complaints about this issue, and I know that only a tiny percentage of people will actually post publicly… I know that Apple has got to be well aware of this problem and I can’t understand why they would continue to yank their customers around like this. If people notice this known issue and rightfully complain about it, they should just replace their phone with an A1865 model and be done with it.
I’ve had many smart phones over the years, including several different older iPhone models, and none of them had this accuracy problem. There is clearly something wrong with the hardware and I haven’t yet seen anyone complaining about the Qualcomm chip being inaccurate.
If you’re on AT&T make sure you do NOT get your iPhone X from them, get the A1865 model from an Apple store and activate it on AT&T. Its the same price and you’ll save yourself a lot of trouble, I can’t think of a good reason not to. If you’re like me and you got scammed by their false advertising and never even figured it would matter since every GPS device I’ve had for the past decade has performed about the same, make sure you don’t let them talk you into thinking your sub-par Intel chip is OK. This is a $1.1k phone, it is able to combine GPS, GLONASS, Galileo, and QZSS satellite signals, there should be no excuse for such poor accuracy with so many satellites in the sky unless you’re operating in particularly poor conditions, or inside a building or a cave or something. You need to tell Apple this is not acceptable. I assume the Intel chip must be cheaper or something, so they are trying to cut corners, but they shouldn’t be cutting corners (no pun intended) on an expensive premium flagship device. They need to make this right.
