FMB001 reads OBD II Data, for example Engine RPM, Speed, VIN number and so on (it depends on the car model). Also you can get DTC Error codes and clear them, if needed. That's the main difference between FMB001 and FMB010. They also don't have any DOUTs or DINs so you can't connect other equipment to them.
Other options as FMB1YX or FMB20X have DOUTs and DINs, so your tracker has more features. It all depends on your business and what do you want from fleet management device. If the tracking is the main purpose - FMB0 is the easiest option.