Mac OS X installers for GRASS GIS.
For GRASS 7 see Michael Barton's GRASS page.
when updating, for best results drag the existing GRASS application to the Trash before installing the new GRASS.
The installer does NOT check for the frameworks, so make sure they are installed before trying to run GRASS. GRASS requires an Intel Mac, and runs on Lion and above. A few support programs, used by various GRASS modules, are included in the application.
NOTE: Later system version builds will not run properly on earlier systems, but due to limitations of the automated package generation the installer will still let you install it on earlier systems.
See the readme for startup options.
GRASS does not work on OS X 10.11 El Capitan because of the new SIP security. There is a workaround which disables SIP, see Michael Barton's GRASS page for details.
GRASS can be used with R. You should get the latest R binaries (at least 2.3.0), the mini install is sufficient (no C/Fortran for building packages from source). The R.app Package Installer is a handy GUI front-end to the install tools. Install the R GDAL package from the GDAL framework (instructions are included with it). Install the maptools binary package from the CRAN binary repository. Install the spgrass6 from the CRAN source repository. See the GRASS stats page for instructions on use.
For GRASS to run on older systems, download the source and see the included Mac OS X build notes for help on how to compile from source.