Development snapshots
We recommend running the latest development snapshot build to get the latest bug fixes and enhancements. The development builds are updated more frequently than the general releases below.
Upgrading from an earlier version of PHD2
Just download and run the installer. There is no need to uninstall the older version first. If you do uninstall the older version, you will remove all your profiles and settings.
Note for Gemini/Gemini2 ASCOM users: PHD2 requires Gemini ASCOM Driver Version 1.0.56.0 or newer.
macOS downloads
For macOS 10.14 Mojave and newer, install the 64-bit version of PHD2. For older versions of macOS, install the 32-bit version.
Linux packages
Patrick Chevalley has PHD2 Ubuntu packages hosted on Launchpad. If you are using another Linux distro, you can build PHD2 from source: Building PHD2 on Linux.