Apps iSmoothRun - GPS distance issues post iOS13 update (SOLVED)

[ftaok]

I'm writing this more to help me remember, but if it helps someone else, then great.

I recently updated to iOS13 on my iPhone Xs. Doing so required me to update my AW Series 2 up to wOS 5.3.1 in order for the Watch app to function properly.

Since then, I've gone on two runs using iSR [latest revision - 6.0.8 (737)]. Same as always, iPhone in my pocket, wait for the iPhone to lock in on a GPS signal and for the AW's HR sensor to kick in before starting. Both runs overstated the distance, and therefore had a faster pace than I should have.

Run 1 - I have regular route that I use when I take my daughter to soccer practice. Google measures the route at 3.28 miles and iSR captures it at anywhere between 3.26 and 3.30 miles. Pretty good. The most recent time, which was the next morning from when I updated my iPhone and AW, it recorded 3.39 miles, which is an overstatement by 3.3%.

Run 2 - My other regular running route is about 3.30 miles (iSR records between 3.26 to 3.33 miles). I ran this route yesterday and it recorded at 3.50 miles (6.1% overstatement).

The last time I had issues like this (about 2 years ago with the same AW, but my old iPhone 6), the mileage was off by +15% or more. Un-pairing and then re-pairing, combined with checking the Motion/Calibration settings fixed it.

So here's what my plan is.

1. I updated to iOS 13.1 last night. On my next run, I'll do everything the same as always and see if that fixes it.

2. If #1 fails, the following run, the next test would be to run using iSR on just the phone.

3. Lastly, I'll try running with iSR just on the AW.

4. If all that fails, I'll un-pair then re-pair

So there it is. That's my plan. I'll update this over the next week or so as I get my runs in.

 

[ftaok]

Here's an update on Run 3. My AW had an update available for wOS 5.3.2, so I did that. I also made sure to restart both my iPhone and AW before going on my run.

Run 3 - same route as I did for Run 2 (typically records as 3.30 miles). Since I updated to a new wOS version, I decided to stick with my normal procedure, which is to start my run using iSR on my watch, after making sure the GPS and HRM are working properly. Had a slight hiccup at the beginning due to Autopause not working the right way, so the start of the run was delayed for about 25 yards or so.

The distance recorded was 3.33 miles, which is within the typical spread that I usually see. The mile markers were in the right spots, on the GPS map. I was expecting to see the mileage on the lower end of the range, due to the issue at the beginning, but I guess it's not off by too much.

I'm going to run tonight using the same procedure and see if everything is back to normal.

 

[Monkswhiskers]

Thanks for the info, I use the native app and also Workoutdoors, I run the same 10k route and the difference each time is negligible which is impressive considering gps is not an exact science.
When I first bought my series 3 (Jan 18) gps was awful for about a week, 30% out, but then improved. I am now on a series 4 and reckon gps accuracy is as good as most of the watches out there. Maybe Garmin 935/45 are the best but the AW is certainly good enough for me.

 

[ftaok]

Another update, and unfortunately, no resolution yet.

Run 4 - Soccer practice night, so I did the 3.28 mile run. The distance recorded as 3.43 miles (4.5% overstated). Very disappointing considering the promise that Run 3 showed.

I decided to bite the bullet and un-pair/re-pair my iPhone and AW. When I re-paired my AW, I decided to set-up as new, instead of using the back-up (BTW, total pain in the butt to re-set everything the way I had it). I had the opportunity to use the stock app to do a few Outdoor Walks to calibrate the GPS.

Run 5 - Soccer practice again, so I had a chance to do the 3.28 mile run. The distance was recorded as 3.35 miles, which is a 2.1% overstatement. That's not too bad and it's better than both Runs 1 and 4.

I'll have to experiment on my next two ones. I'll run using iSR on the AW (with the iPhone disconnected) on one of the runs. On the other run, I'll use iSR on the iPhone without the AW. That way, I can see if it's an issue with one of the GPS units.

Note that on all of the runs, the map that is generated is fine. It's just that the mile markers are showing up 3 to 5% sooner than they should.

Here's and example:

 

[ftaok]

I just noticed something when looking at the two route maps above. The bad one (#1) is very jagged whereas the good one (#2) is relatively smooth. I wonder if something changed in iOS 13 that reduced the amount of smoothing going on with GPS reliant maps???

I decided to look at the maps of the runs prior to updating to iOS13 and the ones after. All 5 runs after iOS13 are noticeably more jaggy than the ones before.

There's an option in iSR for Smart Sampling that looks like it may help.

 

[ftaok]

Final Update

I went on run this morning using iSmoothRun with the Smart Sampling option turned ON.

My route typically records as 3.3 miles and using the USATF mapping function, it shows as 3.27 miles. Finished the run and it logged as 3.28 miles. The mile markers showed up in the expected spots.

I'm going to classify this mystery as solved. Although I don't know what changes occurred with the update to iOS13 that affected the way iSR uses the GPS data from my iPhone, I do know that the Smart Sampling feature solved it.

I guess if you're having issues with your running app overstating your distances, check to see if they have a feature that smooths out the GPS waypoints so that it's not thinking that you're zig-zagging all over the street.

 

[Chuck Turner]

Great information and thanks for posting. i wanted to provide you when update on my experiences. I was having the same issues you describe after getting an iPhone 11 and upgrading to iOS 13.3 beta. Your post helped me do a lot of testing. Yesterday, I discovered something interesting.

When I was using my old phone and Apple Watch, I had a running route that always registered 3.71 miles. With the new phone, everything was either over by .13 miles or under approximately .1 miles. Finally, yesterday, I was able to hit exactly 3.71 miles. What I did that was slightly different than your solution was to put my phone into airplane mode, leaving Bluetooth on so it connected to my Apple Watch. I also made sure my phone was not in its case when I put it in my arm band and turned off Wi-Fi on the Apple Watch. This allowed me to still control my music on my watch and use the iPhone as my GPS source. For whatever reason, this actually ended up giving me the best result. I am thinking it is something in the new GPS chip, or whatever, that is using cell towers and Wi-Fi which is really messing up GPS accuracy in Ismoothrun.

Hope this helps you, or anyone else having this similar issue.

Cheers,
Chuck

 

[bp328i]

While I haven't used iSmoothRun yet I have tried about 5 different run tracking apps to try to find the best one (new to the AW and iPhone). Using AW S5 LTE and iPhone 11 Pro Max.

I always run with my phone in my pocket and earbuds in. After many many test and much research what I have found is if your AW is connected to your iPhone then the GPS from the iPhone is used if not the GPS from the AW is used (which is probably common knowledge for most).

Whenever the GPS from the iPhone is being used it looks like I'm running zig-zags (unless I'm using the built in run tracking app) all over the place and is basically useless. Now when I turn off Bluetooth on the AW so it forces the GPS in the AW to be used and my Airpods Pro are still attached to my iPhone my track is about as accurate as you can get on all of the apps I have tried, even in the built in run tracker.