Hello.
Iยดm from Portugal.
Now my main activity is in road and rail design.
I work with Autocad, ISPOL, and soon begin with Bentley PRT.
Iยดm also a surveyor (not much now)
In part-time i do some programming.
You could visit one of may App for land surveying calculations...
Also maintain a blog about this issues.
http://jcoimbras.blogspot.com.es/
https://play.google.com/store/apps/details?id=com.rfo.Topografia
Thoughts