Apple watch GPS issues during workouts

Discussion in 'Apple Watch' started by eyespii, May 3, 2015.

  1. eyespii, May 3, 2015
    Last edited: May 3, 2015

    eyespii macrumors 6502

    Mar 8, 2008
    Anyone else notice that the GPS on the apple watch is quite a bit off? I know it doesn't have GPS built-in and that it uses the tethered iPhone's GPS, which makes the issue even more's my setup.

    I typically track my runs with the Runmeter iPhone app and a Garmin Forerunner GPS watch. Usually, the two are very close to each other - over a 6.2 mile run, they'll be off by maybe .05 miles. Since getting the Apple Watch, I tried to see if I could ditch my Garmin and just run with the Apple Watch and the iPhone.

    Run #1:
    Runmeter: 5.65 miles, 9:00/mi pace
    Apple Watch Workout: 5.17 miles, 9:35/mi pace

    Run #2
    Runmeter: 5.46 miles, 9:06/mi pace
    Garmin Forerunner: 5.47 miles, 9:04/mi pace
    Apple Watch Workout: 5.12 miles, 9:45/mi pace

    What doesn't make sense is that the Apple Watch and Runmeter are *supposed* to both be using the iPhone's GPS - but when I was tracking a workout with just the apple watch, the triangle GPS icon never showed up - is that why they're off by so much?
  2. lchlch macrumors 6502a

    Mar 12, 2015
    Is motion calibration and distance turned on?

    Are you using the outdoor running workout?
  3. eyespii thread starter macrumors 6502

    Mar 8, 2008
    Yes to both.
  4. lchlch macrumors 6502a

    Mar 12, 2015
    Try turning off runmeter. And see if accuracy improves.
  5. eyespii thread starter macrumors 6502

    Mar 8, 2008
    I've tried doing one run with just the apple watch without using runmeter. Of course, I ran an unknown route so i wasn't 100% sure about the accuracy, but I will say that stats "felt" off to me (the watch said that I was running much slower than I felt like I was running). I'll try it with my garmin and the apple watch without runmeter and see what happens.
  6. eyespii thread starter macrumors 6502

    Mar 8, 2008
    Today's run:

    Garmin Forerunner: 5.47 miles, 8:59 min/mi pace
    Apple watch workout app: 5.26 miles, 9:22 min/mi pace

    So, it's a little bit closer without Runmeter on, but still off by a fifth of a mile by the end of the run. Dunno...
  7. e²Studios macrumors 68020


    Apr 12, 2005
    Until it has GPS built in it will never be as accurate as a dedicated GPS watch. I'll stick to my Forerunner and Mio HRM for training, I need accuracy.
  8. Julien macrumors G4


    Jun 30, 2007
    For some reason if you are using an App that is actively using GPS like Runmeter then your :apple:Watch will not use GPS.
  9. Moria macrumors regular

    May 7, 2005
    Glasgow, Scotland
    I think OP needs to go out and do the same run twice to test it. Get them done back to back as well to save time. And keep up that 9 minutes per mile pace for both so we don't have to wait too long. :)
  10. dhy8386 macrumors 6502a

    Aug 13, 2008

    This is incorrect. Location for all apps and the AW since its tethered to iPhone is provided by CoreLocation, a framework on the phone for gathering location data. No app has direct access to the GPS. When you want location info you make an API call and the phone returns the data. You can have 5 apps open all using GPS and the AW. It doesn't affect accuracy as it's just asking phone to return positional data.

    OP, the AW doesn't actually use GPS to determine position. If you select outdoor workouts from the workout app (run walk cycle), it will use GPS data to improve the accelerometer. This improvement is through better calculation on your stride length. While Apple says calibrate through one run/walk logically to me this will take 5 or more data points for most people whose stride is not consistent every run. For professional runners perhaps less.

    I would do a few workout runs on various terrains and then see if the AW accuracy improves.
  11. johny979 macrumors regular


    Oct 13, 2014
    I'm having same issues. I usually run with my TomTom Cardio and now with watch I think the distance and pace are wrong. Maybe is neccesary more runs for watch knows my strades, but I think if I run with iPhone, the accuracy are perfect, but no

    So if anytime I want run without my iPhone, the training is a joke
  12. TigerStephie macrumors regular

    Jun 27, 2010
    Thank you for the info! So the watch is not constantly finding GPS then which would make sense to why it has to "learn" and why there's no map data. I just wish apple would let you snooze to use the phones GPS and get map data. Or let third party apps use the HRM... But I went on a run the other day with just run meter since I don't want to have to start two apps all the time. And because I didn't have the workout app running I don't think it counted as many calories or exercise time...

    Nothing is perfect I guess
  13. PatrickNSF macrumors 6502


    Jan 24, 2011
    I've logged 51 miles during seven runs with the Workout app in the past week I've had the Watch. I've also tracked three 2-mile dog walks with the Workout app.

    I've carried my iPhone 6+ in my running belt. For two of the runs, I also wore my Garmin 620. At the worst, the mileage was off by 0.1 for a 7-mile run. I don't know how the Watch is pulling the data, but the GPS data has seemed accurate for me. I haven't been running any other apps on the iPhone that use GPS. And I haven't tied any of the other running apps on the Watch, as I want HRM data without wearing a strap.

    Hope that helpful.
  14. eyespii thread starter macrumors 6502

    Mar 8, 2008
    Did you notice that the distance tracking on the watch got more accurate the more runs that you did?

    I was really excited about being able to ditch the clunky HRM strap and just use the Apple Watch, but unfortunately my 3rd party running apps can't access the data :-(. Doesn't seem like I'll be able to ditch my garmin either if the GPS tracking on the watch doesn't improve.
  15. tonyau, May 7, 2015
    Last edited: May 7, 2015

    tonyau macrumors member


    Sep 27, 2011
    More issues

    We have been trying out the watch for walking and I am not happy with the result. As you can see from the table below, we have done 2 routes with and without the phone and every walk has clocked a different distance. There should be no difference with the distances between me and Emile as we are walking the same route at the same time.

    Something seems seriously wrong.

    Route 1
    25/4 4.08km with iPhone
    27/04 4.41km
    29/04 4.28km with Nike Running
    4/05 4.72km with iPhone
    6/05 4.37km with iPhone

    25/4 4.14km with iPhone
    27/04 4.25km
    29/04 4.34km
    4/05 4.33km
    6/05 4.21km

    Route 2
    28/4 4.14km
    5/05 4.18km with iPhone
    7/05 4.08km with iPhone

    28/4 4.01km with iPhone
    5/05 3.99km
    7/05 4.12km
  16. Julien macrumors G4


    Jun 30, 2007
    This does sound more plausible and I was skeptical of the 'no access' claims that I read. However my on running experience seemed to confirm this. I wish Apple would change to using full GPS mapping when GPS is available. I vary my running speed (stride length) depending on the run and this makes my :apple:Watch less reliable.

    I use my Garmin as my 'real' running recorder and use my :apple:Watch as my fitness recorder.
  17. PatrickNSF macrumors 6502


    Jan 24, 2011
    Distance measurements for me seemed pretty close during my initial runs. So far, each of my (as of today) eight runs and numerous dog walks have recorded distance that are good enough for my purposes.

    When I start training again for my next marathon this fall and need to pay more attention to pace, strides, Yasso 800s, hill repeats and all rest, I'll likely use my Garmin 620 as my primary tool, but just for that specific run. I'm satisfied with the Apple Watch for all my other activity tracking.
  18. Break81 macrumors member

    Apr 21, 2015
    no cycling data

    i have a problem with outdoor cycling. The watch is only counting calories and time but no speed or distance. It totally works with running and walking.

    any ideas?

    Attached Files:

  19. extricated macrumors 6502


    Jul 14, 2011
    I've only done a couple using both the Apple Watch workout app and the Nike Plus app (which supports Apple Watch). Very similar data points.

    Not sure what my final solution will be.
    I'm not crazy about fumbling with launching two apps from my watch while starting a run. I really like the simplicity of Apple's offering, but I have a few years invested in my Nike data and don't want to just ditch it.
  20. lchlch macrumors 6502a

    Mar 12, 2015
    Did you bring your phone with you?
  21. daydayvol macrumors regular

    Sep 16, 2012
    I don't have my watch yet but this is where I stand as well. I have thousands of miles on the nike plus app and would like to just continue using that app on the phone and watch. Apple has me cornered until they let developers use the heart rate monitor b/c I feel forced into using the apple workout app. Maybe by June they will give access to third party apps.

    All of the reports about the watch not showing the correct distance doesn't really bother me because I tend to run in the same places and know the distance with or without GPS. I do wish apple would allow the user to fix the distance after a run because that would just help with the calibration process imo.
  22. Break81 macrumors member

    Apr 21, 2015

    of course!
  23. Ries macrumors 68020

    Apr 21, 2007
    Wouldn't put it past Apple to lower the GPS update rate to the watch and try to interpolate using the accelerometer between the points to save battery. Each time you turn, it properly guesses wrong and smoothes the turn causing it to be a "shortcut" of your real distance. Either that or a calculation error in the filters calculating distance and speed.
  24. BD1 macrumors 6502

    Jun 27, 2007
    I think Apple is doing something like this. I did a 26 mile outdoor cycle workout yesterday and the results exactly matched prior rides without the AW. But cycling is not doing any calibrating.

    While running it seems to be doing something like what you suggest. Also Pace seems off during the run but final Pace is a bit more accurate. During my bike ride Speed and Distance were spot on a different points but there is no calibration going on.
  25. tivoboy macrumors 68040

    May 15, 2005

    I was having similar issues at the start, but having done about five long walks now with the iphone in my pocket (and also using motionx on the iphone) the watch seems to give pretty much the exact same distances as motionx and my garmin forerunner. Maybe it's because I'm doing the same walks, but at least it is getting very consistent.

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