UPDATE: The instructions in this article no longer apply for installing QGIS 3.x versions. The download page provides access to the required installers and the QGIS download link for a variety of operating systems: Windows, Mac, Linux, BSD, and Android. To install QGIS on a Mac, the first thing you need to do is visit the QGIS download page. More information about QGIS is available in the article Getting Started with QGIS. QGIS offers compatibility for a variety of GIS vector and raster file types (such as shape files, KMLs, and GeoTIFFs) so it works well for those that need to migrate back and forth between other GIS and mapping platforms. Anita Graser provides an overview to the QGIS ecosystem which includes a desktop GIS component, cloud hosting, and mobile application. QGIS is an open source GIS software package that can be freely downloaded.
One of the best user friendly options out there for Mac users who want to run GIS software natively is QGIS.
