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SpEe1113

macrumors regular
Original poster
Apr 24, 2015
117
42
Florida
Hey, so I know there was another thread on the watch's GPS accuracy, but here's a direct comparison vs another fitness tracker... I ran this morning wearing both and have already "calibrated" the Apple Watch on a 20 min run with the phone. Running the latest 1.0.1 was hoping the accuracy would be a bit better... here were my findings... Apple Watch on left arm, TomTom on right...

Actual Route Distance (via MapMyRun online pin drop mapping): 2.38 mi
Apple Watch Distance (with phone connected, using a distance goal): 2.32 mi
TomTom Watch Distance (using a distance goal): 2.35 mi

It seems the TomTom is right in the middle...Just surprised the Apple Watch isn't a bit closer at this point...it is an improvement from 1.0.0 which was logging my route at 2.28.

Has anyone else checked this to compare the route? I would think when running with the phone it should be spot on accurate since it uses the map, no?
 

profets

macrumors 603
Mar 18, 2009
5,114
6,146
Hey, so I know there was another thread on the watch's GPS accuracy, but here's a direct comparison vs another fitness tracker... I ran this morning wearing both and have already "calibrated" the Apple Watch on a 20 min run with the phone. Running the latest 1.0.1 was hoping the accuracy would be a bit better... here were my findings... Apple Watch on left arm, TomTom on right...

Actual Route Distance (via MapMyRun online pin drop mapping): 2.38 mi
Apple Watch Distance (with phone connected, using a distance goal): 2.32 mi
TomTom Watch Distance (using a distance goal): 2.35 mi

It seems the TomTom is right in the middle...Just surprised the Apple Watch isn't a bit closer at this point...it is an improvement from 1.0.0 which was logging my route at 2.28.

Has anyone else checked this to compare the route? I would think when running with the phone it should be spot on accurate since it uses the map, no?

I also use a TomTom watch (Multisport Cardio) for running (and swimming, cycling). I've done many runs with both (AW on left wrist and TomTom on the right). A few times the Apple Watch has been accurate, but most of the time it's not even close. Good 10-15% off.

There's a lot of threads about this so I'm not going to rehash too much, but when carrying the phone as well the Apple Watch doesn't seem to be using GPS directly. I've barely ever gotten an accurate distance (or pace during the run) when I've had both watch and phone on me.
 

twisted-pixel

macrumors 6502a
Sep 13, 2009
886
76
San Jose, CA
My AW is always under by about 5% per mile. My guess is because I do a lot of trail running meaning that my cadence and distance per step are not exact each time.

100 steps on a flat road are not the same as 100 steps on a hill climb, despite the cadence being the same...hence the delta between phone and watch.

It seems stupid to me that, even when I have my phone with me, the watch wont use the GPS but instead tries to 'guess' my distance based on a step pattern that it assumes remains constant through my run.
 

SpEe1113

macrumors regular
Original poster
Apr 24, 2015
117
42
Florida
My AW is always under by about 5% per mile. My guess is because I do a lot of trail running meaning that my cadence and distance per step are not exact each time.

100 steps on a flat road are not the same as 100 steps on a hill climb, despite the cadence being the same...hence the delta between phone and watch.

It seems stupid to me that, even when I have my phone with me, the watch wont use the GPS but instead tries to 'guess' my distance based on a step pattern that it assumes remains constant through my run.


I wonder how long the watch "learns" or "calibrates" because my run this morning along the same route clocked in at 2.34mi (actual distance 2.38) and I used a time goal instead...interesting...not much consistency, that's for sure! Let alone accuracy... but I think being 0.04 off the actual distance is a bit more "acceptable" although, it should be spot on if it's using the map from iPhone to track...
 
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