I am wondering if I could get a GPS antenna to connect by Bluetooth (or maybe by a cord) to my mobile phone so I can have a little more accuracy on my phone. It is frustrating when the gps jumps me from getting closer to the cache to a half mile away when I walk by water, down a hill, or between some rocks on the trail. I know I could purchase a GPSr, but I'm new and trying to find a less expensive way to get me a little closer to my target. My husband calls me obsessed, but I enjoy walking with a purpose more than just walking. Thanks!