After upgrading to macOS 12.3 and iPadOS 15.4, one of my Macs refused to work with Universal Control. I did a lot of digging and figured out everything I could about when it does and doesn’t work.
- Both devices must be signed into the same iCloud account
- Your devices must be compatible with the feature
- Bluetooth must be enabled on both devices.
- WiFi must be enabled on both devices and connected to the same network. Even if you use an Ethernet as the preferred connection, the WiFi must still be on.
- Handoff must be enabled on both devices:
- macOS: System Preferences>General>Allow Handoff between this Mac and your iCloud devices
- iPadOS: Settings>General>AirPlay & Handoff>Handoff (toggle on)
- Universal Control must be enabled on macOS: System Preferences>Displays>Universal Control…
- Allow your cursor and keyboard to move between any nearby Mac or iPad (must be checked)
- Push through the edge of a display to connect to a nearby Mac or iPad (optional. If not checked, you can still manually link it through Control Center>Display>Link keyboard and mouse to:>[Device Name])
- Automatically reconnect to any nearby Mac or iPad (check if you want to, optional)
- Universal Control must be enabled on iPadOS: Settings>General>AirPlay & Handoff>Cursor and Keyboard (Beta)
- macOS Firewall must allow incoming connections from Universal Control.
- System Preferences > Security & Privacy > Firewall > Firewall Options > “Block all incoming connections” must be off.
- “Universal Control.app” must be listed and set to “Allow incoming connections”. It may not be if you have unchecked “Automatically allow built-in software to receive incoming connections”
If after all that it still doesn’t work for you, check your router’s network firewall settings. I expect Universal Control will not work on public or hotel WiFi networks that restrict communication between devices on the LAN for security reasons.
Other issues you may encounter:
Scrolling direction differs between your connected devices
These settings should be set the same way on your devices. Set them both either on or off, as you prefer.
- macOS: System Preferences>Trackpad>Scroll & Zoom> Scroll direction: Natural
- iPadOS: Settings>General>Trackpad & Mouse>Natural Scrolling
If these are different, then you will have a confusing time switching scroll directions as you move between devices.
Cannot use Universal Control while using the iPad as Personal Hotspot
The Personal Hotspot feature disables WiFi on the iPad while any device is tethered to it, so Universal Control does not work. Both devices must be on the same WiFi network.
Universal Control can Interfere with Sidecar
If you frequently use Sidecar to use your iPad as an extra display, I recommend disabling the “Push through the edge of a display…” option. If you are using Sidecar, then accidentally push against the edge of that display, Universal Control will take over and disconnect the Sidecar display.