Bosch flow elevation gain inconsistency

[Dave238]

I've noticed after 2 years of using the Bosch flow app that elevation gain can be inconsistent. I have an 8.5mi local ride that I've ridden 50+ times. Same route, but flow can show a range of 780 ft gain one time and 1100 ft another time. I have not done a mental correlation to weather (temp comparisons). I had an old Note9 phone and now a S26Ultra and notice still the same discrepancy. As I understand it, either barometric pressure and gps of the phone is used to derive the elev value. I have run another app (but not extensively) at the same time and gotten a little more consistency in that app (onX or trailforks).

Anyone else notice this? Any phone settings that would improve the accuracy?

 

[RustyIron]

The reported elevation would be different depending on sampling rate, thresholds, and noise filtering. Imagine measuring the elevation change using a couple yardsticks and a level. You'll get different results depending on your measurement methodology. Neither result will be wrong.

 

[Dave238]

The reported elevation would be different depending on sampling rate, thresholds, and noise filtering. Imagine measuring the elevation change using a couple yardsticks and a level. You'll get different results depending on your measurement methodology. Neither result will be wrong.

But if I'm using the same phone, the same bike, the same app, the same trail and get a 25%-40% variation, I don't understand what is causing the different "sampling rate, thresholds, and noise filtering".