Getting some measurement discrepancies in Field Maps for hosted feature data that I don't seem to have any control over. For example:
The built-in length display of the feature under its title in the popup, and from the list of selectable features when tapping near multiple features, is displaying a polyline length of 172.4m.
Meanwhile, the Shape__Length field is displaying 185.42. This same length of 185.42 is also displaying on ArcPro in the attribute table.
This discrepancy is also occurring for polygon features regarding their area.
These discrepancies seem to sit around a 7% difference in length/area across all features. As expected, this persists if I change units on the Field Maps app. What's going on here?
Currently running Field Maps 24.2.2, Build 1512 on Android version 14.
I would assume this has something to do with the map projection. The built-in Shape__Area will be calculated based on the shape's spatial reference; the other is calculated on the fly in the map you're using.
Try creating / moving a feature near the poles or the equator. Does the percent difference change with latitude?