I have Viamici. It isn't free (or cheap) but it is quite interesting if there are posted maps of the trails where you hike that you can take a picture of with your Droid. With two input points it will show you on your trail map picture where you are. You can zoom & pan the picture. Of course it requires GPS be on to see that but you can turn it off while hiking and just turn it on when you need a location fix.