My experience with US trucking is it used to be done on paper. It probably still uses a lot of paper but electronic systems are common. The paper logs would be reviewed by the employer but could also be checked at road checkpoints. They could be easily pencil whipped, hence the move to electronic. There is a constant drive from the logistics side to get better telemetry about shipment speed and from governing bodies to maintain safety. Local storage of data isn't too feasible for access to that data when the trucks most at risk of violating limits are the ones that rarely go home. I guess it could have a standardized wired interface at inspection like obdii and checked as often as paper logs, but wired mobile devices are a rarity in any field these days.