Luna Secondary

Luna Secondary is a macOS app for extending a workspace to a second display. Astropad describes Luna Display as supporting computer-to-iPad, computer-to-Mac, and Headless Mode setups; this Homebrew entry installs the Luna Secondary app, not the Luna Display hardware.

• The official product page describes using an iPad or another Mac as a secondary display for a computer.
• Headless Mode is described as using a Mac or iPad as the main display for a Mac mini or Mac Pro.
• The Luna Display setup uses apps on the primary and secondary devices, which connect over an existing Wi-Fi network or USB cable.
• The product page says Luna Display hardware must be plugged directly into a computer and does not work with adapters.

Install the app on macOS with brew install --cask luna-secondary. The product page’s Luna Display setup also calls for Luna hardware and apps on both devices; installing this app alone does not provide the hardware. Check the official requirements for the particular devices in your setup.

Sources: Luna Display · Homebrew cask