Behold the Iter Avto, the world's first automobile navigator, created in 1930.
Of course, it didn't have voice prompts and GPS, but we all need to start somewhere.
The principle is quite simple. The screen manually scrolls paper maps that are attached to a cable that similar to a modern mechanical speedometer. Thus, the scroll rate of the map is proportional to vehicle's speed.
The problem is, if a motorist made a turn, he would have to change the map and find it on his current location.
Oh well. Nothing is perfect.
Ten years earlier, way back in 1920, you could find the Plus Fours Routefinder. This manual "navigator" resembled a clock and consisted of paper maps and two wooden handles that needed to be scrolled manually.