Is the GPS accurate?

[papacliff]

I have a Charge HR, I'm running the app on a Samsung Galaxy S6 with Android 5.1.1.

I was using the "Map My Walk" app to track my morning walks. I started to use the Fitbit and noticed a discrepancy. Here are two screenshots from a walk. I had both apps running concurrently on the same device.

On the left is Map My Walk, on the right, Fitbit. There are no significant differences in the routes, yet there is a total difference of almost a quarter mile. While the total time is the same, this greatly affects the pace. If both apps are using the phone GPS, why would this happen? Is there a way to know which one is correct?

Thanks. 

[billreitan]

I too have a charge. My nightly walk show 5.04 miles using my gps but my daughters apple watch shows 5.3 miles. To me thats a big difference. Wonder what it could be ?