These are alternate, semi-official QGIS packages. The installation is separated into a few installer packages, and components shared with other software or that are useful by themselves are installed outside the QGIS application. QGIS 3 uses Python 3.9, it does NOT use any other Python distribution. The correct Python installer is included on the QGIS disk images.
Official all-in-one packages are available from qgis.org.
Install the Current version to stay up to date on features. Install the Long Term Release version for feature stability for a year. Note that the QGIS application name may conflict with the all-in-one build, it is possible to rename either, but some functions may not behave properly.
Install Note: OS X security may block installation, as I’m not an “identified developer” (ie not paying Apple). There is a simple way to force it to install – right-click the installer file and select Open, this will trigger an extra option in the security warning to install it anyways. You only have to do this once, the system will remember the QGIS installer for any future installs (new major versions may reset this). The same trick may be needed to run QGIS the first time.
Include all necessary packages. See the GDAL framework page for version info.
- QGIS 3.16.5-1 LTR [310.5 MiB] 2021-3-20 (OS X 10.13 High Sierra+)
- QGIS 3.18.1-1 [312.3 MiB] 2021-3-20 (OS X 10.13 High Sierra+)