Accuracy of cumulative elevation gain and loss


#1

I found the cumulative elevation gain and loss statistics calculated by Trails are very inaccurate.

For example, in the following track, the elevation changes are about 130 -> 350 -> 170 -> 400 -> 290 -> 365 -> 130 (m).
https://trails.io/s/mu4bpr/

If I calculated the elevation gain and loss manually, they are +220, -180, +230, -110, +75, -235, which sum up to 525 m of ascent and decent.

However, the number that the Trails app gives me are 1020 m ascent and 1036 m descent.

The numbers calculated by Trails almost double the amount of manual calculation.

I hiked the route personally so I know the ups and downs are quite simple like the numbers above. There was not much tiny ups and downs. I think the numbers calculated by Trails are too far-off from reality.

I recorded my hiking routes with the recommended Automatic mode and “Smart” accuracy setting. I also tried different settings but couldn’t see obvious positive improvement.

I know this calculation is a very hard. The phone might record lots of inaccurate points that are far from the actual location, especially when there are trees.

However, I really hope Trails can provide numbers that are more meaningful.

Thanks.


#2

I have been reporting similar issues for a while now, probably about a year. I have had some luck turning off “automatic mode” and tweaking the required accuracy and distancefilter myself. My best guess it that the app is not smoothing the raw GPS data enough — my elevation graphs are always extremely jagged, even when I am hiking straight up hill. For the time being I have resorted to using Trails to organize my tracks, not to record them. I would not expect this issue to be resolved in the near future.


#3

Hi @Seanndaly,

Thanks for sharing your experience. :pray:

Using other apps to record GPS tracks sounds like a practical workaround.

Do you have any recommended apps?


#4

Gaia GPS is a good one for the iPhone; for the Apple Watch I really like WorkOutdoors. I have not found any GPS app that can match Trails’ beautiful design, however, which is why I am still using it for storing and organizing tracks.


#5

Thanks, @Seanndaly. I’ll give those a try! :smile: