GPS and Maps

Every GPS unit out there that supports mapping only supports "vector" maps. These vector maps are not scanned images. Think AutoCAD drawing and it should help. These type of maps take up less memory than raster(or scanned) maps like the ones Maptech sells. Now you can buy software that provides vector maps for GPS units. However, there's no standard format. So each GPS manufacturer provides their own format. So if you buy a Garmin unit that supports maps, then you would need to purchase their map software called MapSource. If you buy a Magellan unit, then you would need to buy their map software called MapSend.

It is possible in a round-about way of getting raster map support for GPS units. How it works is you buy a PDA(Palm or PocketPC) and then run a mapping program on it that supports GPS units. You copy the maps that are supported by the mapping program to the PDA and then connect a GPS to the PDA via a cable, Bluetooth GPS or compact flash GPS. The mapping software just communicates with the connected GPS unit and displays your position on the map, along with routes, tracks, etc. Most GPS mapping software give you the same functionality that the GPS unit does.

Worth a thought.