A navigation device including a device, provided for mobile use, having input and output means, having a processor for processing software, having a navigation software for position determination and for route computation, and having a first interface for transmitting data into and/or out of the device, wherein the first interface is developed, in the operation of the device in a motor vehicle, to read operating and/or sensor data of at least one vehicle component into the device via a second interface and a data carrier having a navigation software for use in a device provided for mobile use, the navigation software including a software module which utilizes operating data, read in via an interface of the device, of a vehicle in which the device is operated or sensor data from sensors situated in the vehicle, for position determination or for determining a state of motion of the vehicle. The present invention has the advantage that navigation devices based on devices provided for mobile use, especially so-called hand-held computers, and also PDA (personal digital assistant), mobile radio telephones and the like are improved. In particular, the accuracy of the position determination in such navigation devices is decidedly improved.