How does the app’s accuracy match against a built-in taximeter’s accuracy?

OBD:
With OBD data, we get a distance calculation accuracy that is the closest possible to the distance measured by the car’s odometer.

GPS:
You need to be aware that GPS-based and classical meters can, by the nature of physics, never calculate the same distance for the same trip.
Why is that? Classical meters measure the number of wheel rotations to calculate the distance. Due to tire degradation this gets more and more imprecise over time and the measured distance increases. That’s why calibration is needed.
Classical meters tend to calculate a slightly higher distance compared to a GPS-based meter.
We have a complex filtering and enhancing algorithm in place. It decides, based on previous signals, if a newly received signal should be considered, rejected or modified.