Inconsistant accuracy with GPS

[LDaleRunner]

Today I went for a 5 mile run. My Ionic recorded the run as 5.2 miles. I have had gps running watches for over 10 years now and instead of the gps getting more accurate, it seems to be getting less accurate. I understand that the accuracy may be within 20 to 50 feet but this is consistently off by more than 1000 feet. In this day and age when the government can tell from my smartphone gps if I am standing within 6 feet of another person why can't my gps watch be at least a little closer to this accuracy? One question I have is at what point does my Ionic update gps data? I assume it is when I synchronize it with the Fitbit app on my computer.

[Giampi71]

Hello @LDaleRunner 

You might want to read my reply to a similar question here.

[LDaleRunner]

Hello @Giampi71,

  Thanks for your response. I am surprised to hear that the Ionic would use stride to calculate distance when it has built in GPS. How does it calculate distance when the activity is bicycling? If it uses stride I can see why it would be off since a persons stride can change depending upon how fast they are running. In the past I had a Motorola GPS watch and that thing was consistently accurate unfortunately they discontinued that watch.

[Giampi71]

I understand your surprise @LDaleRunner but Fitbit has implemented this strange algorithm for some reasons.

My tests shows that the stride calculation helps to compensate the GPS accuracy while running at constant pace but has many limits when you have variable paces (such as interval training or walks/hikes)