Guides
How GPS speed and trip logs actually work.
Explainer
Why your car's speedometer reads higher than GPS
The dashboard is legally forbidden from under-reading, so it is calibrated optimistic on purpose. What the rule says, how GPS derives speed from Doppler shift, where each one is the weaker instrument, and how to measure your own car's offset in ten minutes.
How-to
How to record a GPS trip on Android without losing it
Half-recorded drives are almost never the app's fault — they are battery optimisation killing a background service. The permissions to grant, the two separate battery settings to change, where to put the phone, and how to read the shape of a failure when one happens.
Reference
What belongs in a mileage log, and why each field matters
The five fields a mileage log actually needs, why the fuel price has to be frozen at the day of the drive, why the rate belongs to whoever pays rather than to the car, and when a CSV beats a PDF.
Reference
Trip stats explained: moving time, average speed, elevation gain
Plain definitions for every number a trip log produces, with the thresholds that decide them: moving versus stopped time, why average speed is not distance over total time, why elevation gain is not a net change, splits, speed zones and the smoothness score.
Record your next drive
Speedometer One is a GPS speedometer that keeps the logbook too. Free on Android, no account.