Mac-to-Mac Mode: Using your Mac as a Second Screen with Luna Display 

Feature Overview

Mac-to-Mac Mode is a new feature in Luna Display for users who want to use any extra Mac computer as a second display or extension of their primary Mac computer. 

Users may use any combination of Macs in Mac-to-Mac Mode. For example, the following are acceptable combinations of Mac-to-Mac Mode:

  • iMac + MacBook Pro
  • MacBook + MacBook
  • Mac mini + MacBook (use your MacBook as the main display for your Mac mini)

Minimum Compatibility Requirements

  • The Primary Mac must be a 2011 or later and requires macOS 10.11 El Capitan or later
  • The Secondary Mac must be a 2007 or later and requires macOS 10.8 Mountain Lion or later
  • You will need the latest version of Luna Display on all devices. Free download available here:
  • Internet connection is necessary as USB is only supported for Mac-to-iPad Mode at this time

Mac-to-Mac Features

  • Trackpad support for both computers
  • Keyboard support for both computers
  • Compatible with macOS 10.8 Mountain Lion or later. See details belowab

What You’ll Need

    1. Primary Mac: This is the main Mac you will be using — the host Mac from which all of your programs and windows will be projected. The Primary Mac must be a 2011 or later and requires macOS 10.11 El Capitan or later.a

    2. Secondary Mac: This will be your extended display — the receiving Mac onto which you may drag any of your program windows. The Secondary Mac must be a 2007 or later and requires macOS 10.8 Mountain Lion or later.b

    3. A reliable network connection: Mac-to-Mac Mode will work whether you are working wirelessly via WiFi or tethered to your router.

    4. Luna Display: You will need the Luna Display dongle, and the latest versions of the Luna Display apps for both the Primary and Secondary Mac, which are free and available for download at   

      If you already have the Luna Mac App and recently downloaded the latest version from our site, you will need to replace the Mac app to update. If the prompt in the image below appears, select 'Replace'

How to Connect

  1. Make sure both Macs are securely connected to the same reliable network.
        1. If the Macs are using different internet connections, they will not be able to find each other. 
        2. You may connect via WiFi or with an ethernet cable.
    1. Open up the regular Luna Display Mac app on whichever Mac you have chosen to be your Primary Mac.
          1. If you're running macOS Mojave or later, you may be asked to change your Accessibility settings under Security & Privacy. You only need to do this once. Every time afterwards, the app will load to the Luna Display Home screen.
          2. For more information on running Mojave or Catalina with Luna Display, see our guide: Getting Started with Luna Display

    2. Open up the Luna Display Secondary Mac App on your Secondary Mac 

    3. When both apps are open and the computers are connected to the same network, your Macs should automatically connect! If the Macs do not automatically connect or you have selected Wi-Fi Manual Connect, skip to the next section: Using Wi-Fi Manual Connect.
    4. Voilà! You are connected! Have fun :)  

    Using Wi-Fi Manual Connect

    1. Select Wi-Fi Manual Connect on both the Primary and Secondary Luna Display Mac App 
    2. A code will appear in the app on your Primary Mac

    3. The same code will appear in the app on the Secondary Mac with a few digits missing

    4. Enter the last few digits of the code from the Primary Mac into the Secondary Mac to complete the number sequence so that they are matching

    5. Press Connect in the app on your Secondary Mac. Have fun! 


    If you are having trouble connecting

    If you are having trouble connecting, check to make sure that both computers are connected to the same network. If using over WiFi, try plugging either of your computers into the router with an ethernet cable. If you still experience issues, please contact us in any of the ways below.

    Remember, whether you are using Mac-to-Mac Mode or iPad-to-Mac Mode, all devices require the latest version of the Luna Display App for the Modes to work. 

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