Hi @Jane
It took a while to test it, but no, it did not solve the problem. I believe the problem is not in GPS as such, but in the algorithm how a gpx track is recorded and noise analyzed. Noise is immanent to GPS recording, but my particular GPS sensor seems to be more noise-prone, and it simply shows up in the traces.
There is, however, a well-known "noise cancelation" algorithm for GPS tracks known as Kalman filter. An excellent explanation and implementation can be found e.g. here. However, it seems that it is not implemented on Strava side either, and it should, at least as an option to post-process the data.
I've just tested Strava's "Correct distance" option on my recent hike, reported as 15.69 km by my iPhone (the correct distance is some 15.10 km, as previously measured by two separate smartphones), and it made a mess out of it, "correcting" it to 16.98 km. It seems something is seriously wrong there. A properly implemented Kalman filter can only shorten the reported distance, as it filters out all the wobbling, yet I've only seen the option increasing the total distance.
As a workaround for my problem, I ordered a Garmin watch as a present for my upcoming birthday. 😉 And I carry my old phone to my runs (hiking distance is of lesser concern).
