fitbit vs google fit - discrepency in data

[FITwalkerFIT]

when i walk with the google fit app enabled on my android device and my fitbit charge 2, the google fit app will reflect that I have walked 2.5 miles at an average pace of 16.30 minutes per mile.  My fitbit charge 2 wiill reflect 2.1 miles at a pace of 17.45 minutes per mile. same walk, same GPS chip, fitbit charge 2 in walk mode, both enabled and stopped at the same time.  how can there be such a huge discrepencay when the fitbit charge 2 allegedly uses the android GPS chip on the android device as does the android device?  What does the fitbit charge 2 use the android GPS chip for other than producing a map?  How can there be a discrepancy???  Obviously the fitbit charge 2 does not use the android device's GPS chip to log distance or pace.  What am missing??

[HeydyF]

Hey hey hey @FITwalkerFIT! It is great to see new members around! 🙂 Let me explain to you that the Charge 2 and Google Fit app, both use different technologies to track your steps, distance, etc., so we don't suggest you to compare the data recorded by them. On the other side, because of the results that you posted, it looks like the difference still in the normal range. Regarding the GPS, I know that both apps use the same GPS signal on your Android phone, however the algorithms that the apps use are different, and that is why you don't get exactly the same results. I urge you to take a look at the information in this post about how the Fitbit track steps, so you can have an idea about how they work. 

If you have further questions, let me know! 

[FITwalkerFIT]

with all due respect, this is not about algorithims. This is about a
tracker being connected to a mobile device and using the mobile device to
compute distance, time and pace. two devices using the same GPS chip
should agree on the distance, time and pace. That is simple math. there
is a 20%-30% difference in the tracker's math and the mobile device's math,
both using the same connected GPS chip. My guess is that the fitbit
tracker uses stride legnth and not the connected GPS to compute distance
and pace, despite fitbit's claim that it uses connected GPS. there is no
other explanation for the discrepency.

--
Steven Weisbeger

[Rich_Laue]

All the GPS unit does is send points when it has been requested to send them.

The apps are responsible for how frequently they request these points from the GPS chip, and what their own algorithms do with these points. So yes their individual algorithms,  or what they do with the GPS data will affect the reported results.

I have also noticed that if i don't have enough free memory in my phone, the GPS suffers in the Fitbit app. Having a second power hungry app running has detrimental affects on the accuracy of my fitbit app.

Also if both apps tequest GPS data at the same time, one of the apps will get yhe data first. The other one will have to waiy, this wait will increase the time between points.

[FITwalkerFIT]

to suggest that a significant difference in computed distance and pace
between google fit and fitbit is in the 'normal range' is nonsense and a
cover for a product that simply does not work properly. fitbit needs to
own up to the fact that its product is defective and work on fixing it, not
explaining that it is in the "normal range" of error. go back to the
drawing board and stop the excuses. have you followed the price of fitbit
on the stock market?? excuses relative to "normal range" of error do not
seem to work there.

--
Steven Weisbeger

[seymtlqc]

i know from walking the same route several times that fitbit records the time with a pretty good record of how long it takes but google fit added on 14 minutes more.

[Rich_Laue]

Did you manually start the walk, or let the Charge 2 decide @seymtlqc

[seymtlqc]

I just strapped it on and walked. But now I've noticed that since I used
Google fit my time line in Google maps is incorrect. Instead of showing
straight lines of my trajectory, it shows my route as if i was flying home
on a direct line.

[Rich_Laue]

As for as I know your Fitbit account can not be connected to Google fit, even if it could Fitbit would not be able to send a map of your walk to Google Fit.

Was your Fitbit map accurate?

As for the Google Fit map, this might be caused by using to mapping apps at the same time.

[Nolefan32]

There is an app called fittofit that will bridge the two together.

[Laurenhikestaho]

 I did a hike yesterday and my Fitbit says I hiked 14 miles yet my Google Fit says 11. I'd love to know which one is more accurate. This hike had lots of switch backs and smaller steps since it was very rocky with lots of switchbacks as the hike has a 3100 ft elevation gain. My guess is the Google fit wasn't understanding all of the smaller movements to get up the mountain but would love to know! I have the Fitbit  Charge 5