Using My Droid for Sampling

Droid 2 with Ram Mount

I tested my Droid 2 as a GPS for sampling.  I found a free app called Locus Free that I tested today to see how it would work as guidance for soil sampling.  Originally I was led to believe it could display and track a shp file.  I tested that previously and found that if it can display a shp file I could not figure it out.  It does display both kml files and gpx files.  It also will display an aerial photo background, but that is too dark to use in the sun.  The kml format displays very dark and it would be difficult to use in the sun.  Inside the truck, the aerial is fine.

It is not real obvious how to get the files to display.  I place them on the mini SD card in the phone by drop and drag.  I decided that I must need to import them and went that route, but that looked to take me to a way to import online maps.  I finally noticed a load button in the import part and pushed it.  That took me to the SD card.  I had over 2000 acres of soil sample zones in one file, just to see how that worked.  It was kind of slow to load, but it worked in the end.  Once you get the gpx file loaded, you have back out of the import area and go to the tracks feature.  You have to select the tracks you want, and since they are randomly numbered, you want to select them all.  That can be a bit slow and tedious on the size file I had.  I finally found a button on the lower left of the screen to select all with one click.  That helped.   Once your maps are loaded, you need to turn on the GPS.  The button looks like a radar antenna.  You back up to the map screen and you should see your maps.  There may be a delay.  Zoom in close enough to see what you want and you are on your way.  I do carry a paper map too because the gpx map does not have attributes on it.

The Ram Mount worked better than expected.  It is a universal mount so I was not sure.  The phone stayed firm in the mount.  The screen does turn off after about 2 minutes.  Sometimes when I turned it back on, the gps was still on.  Sometimes not.  It is not hard to get it back on, but I would like to figure out how to keep it on.  The app was a big drag on the battery, but it should work with your power cord.  I had trouble getting the power cord to work for me today.  I hope to figure that out. 

So the question is, is this thing useful?  I found that it was useful.  It seemed to be accurate enough, especially if you do not get too close to the borders.  I plan to use it as a back-up system in case something else crashes.  There would be merit in having separate fields as separate gpx files to speed up loading.  I think this might be an inexpensive way to get a start at looking at the possibilities for precision farming.  The app does have mapping capabilities, but I did not test them.  A farmer would need to find someone to convert his field boundary shp files to gpx format.

There is a Pro version for $14.  I have not tested it because the free version does what I want to do.  I do not know if there is a similar app for I-phones.