Came across this app for the ipad and iPhone called Maplets via Bicyclenomad. It looks really interesting and could be handy for making use of local maps such as those produced by Councils and the like.
I played with it on my iPad using local maps and it seemed to work well. It interfaces with the GPS and the maps are downloaded.
No Android version it seems
Could be useful for bicycle touring and of course other riding and walking.