"BackCountry Navigator is an Android GPS app that runs on both Android smartphones and tablets."
I don't want to spend a couple hundred bucks on a GPS unit and then pay even more for maps that should be free. I really seldom need a GPS unit but there are times that having one can simplify finding something or getting back to the car. I have used it in the car to figure out what road junction I am at. I have tried this out and and think I found what I have been hoping somebody would develop in a GPS app. I tried the free version and when it worked, I went ahead and paid the $12 for full functionality.
If nothing else, the free version is a fun toy for the copilot to play with while driving around the back roads.
Simply by painting an area of on an onscreen map, you can download the USGS 15 minute topos (1:24,000) to your phone so it will work if you don't have data service. The downloaded maps I got are the previous generation not the new vector graphic junk. Maps can be downloaded from a selectable list of sources but I got the ones I downloaded from caltopo.com.
Battery life is an issue with cell phones but you can buy a backup battery pack for a couple bucks. I figure the phone battery with a rechargeable dongle battery should last a week if you only turn it on a few times a day. I have a $10 2600mAh Portable USB Power Bank that has just enough juice for one recharge and is smaller than a candy bar.
I don't know if there is anything comparable for iPhone. I've never owned anything from Apple which I consider to be a "you can get better but you can't pay more" sort of operation.
