Proj4

The app Proj4 is a coordinate converter for Android, based on the proj4 coordinate conversion library.

DOWNLOAD: http://marcocorvi.altervista.org/caving/speleoapps/speleoapks/SpeleoApks.html

Coordinates

Altitude (Z coordinate) is always in meters.

The X and Y coordinates can be in meters or in degrees depending on the CRS used. You can use decimal degrees or degrees,minutes.seconds.

Coordinate Reference Systems

Proj4 comes with only a few Coordinate Reference Systems (CRS).

These are stored in an internal database, organized by the country.

If you want to contribute CRS for you country, send me an email.

CRS can also be added by specifying them in the proj4 syntax.

Added CRS are stored in a custom file.

To add a CRS you must give a nickname to the new CRS and write its spec in the proj4 syntax.

For example: "+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0 +no_defs +a=6378388 +rf=297 +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 +to_meter=1

See the proj4 man for details.

Other functions

- Coordinate import from MobileTopographer point list.

- Point visualization on Google Earth, or similar.

- Magnetic declination.

- Point coordinate export to file.

See http://code.google.com/p/topolinux/wiki/Proj4 for further info.

Bug reports and feature requests: marco.corvi@gmail.com

Credits: Antonio Pandolfo for help populating the CRS database