When I compare diagrams from garmin connect and android app the diagram is different. The correct diagram is in the garmin connect web and false diagram is shown on Android app. The Android app has bug in the y-axis and in the x-axis of the diagram. The values in the axis is not linear, they are variable steps. Please garmin fix those android diagrams to be similar as garmin connect web.
I wondered what you meant, so took a look at one of my charts. Elevation axis (y) reads 44,66,89,111,134,156. Looks like rounding errors or integer truncation errors. Should be relatively trivial to fix.
