Look like it does the same as 'BasicGPS' the only difference I can see is that BasicGPS is free.
Give it a try http://www.basicgps.co.uk/.
BasicGPS also links to googlemaps but you would need a sim card and a data plan to keep the costs down.
As for the maps as you are probably aware mapping software is not cheap but these are probably the cheapest for a full package(still not cheap though) http://www.mapyx.com/
Hope this helps