hey all, just downloaded this onto my Samsung galaxy and it works great. It was recommended to me by a friend that works for the forest service. Once you load it, you can download any pdf formatted map into it and us it as a gps/ mapping tool. As long as the pdf has georeferenceing it will recognize it. you can put points, track your steps, add a photo with is linked to the location, and can put different notes, and its constantly keeping track of your location. Pretty cool. You guys should check it out, really cool tool. I used it this last week taking my son deer hunting and it works pretty cool, pretty accurate too! Oh, and it doesn't use data off the phone. If you guys have questions i'd be glad to help, I just started using it myself so i'm not a pro but I can share what I've found.