How to Use Your iPad as an External Mac Display With Sidecar
The new Sidecar feature in macOS Catalina extends your Mac’s display to your iPad. With it, you can use your iPad as a secondary monitor or as a mirrored display that works with Apple Pencil and accessories like a mouse and keyboard.
How Sidecar Works
Once you have macOS Catalina installed on your Mac, you can connect your iPad to your computer and use it as an external display. It works both in a wired and wireless mode.
If you connect your iPad using a USB-C or Lightning cable, the connection is faster and more stable. But for most users, the wireless connection will work just as well. There’s no major lag as Apple uses its own Wi-Fi-based AirDrop-like peer-to-peer connection.
Because of the peer-to-peer connection, Sidecar only has a 10-foot range. If you move to another room, you’ll notice lag and then a warning on the screen asking you to move closer to the Mac.
If you want to use the iPad as a portable display for a Mac around your house, you should look at Luna Display which works on a Wi-Fi network and has a longer range.
Once Sidecar is enabled, the iPad works as more than just a monitor. You’ll see a sidebar with controls and shortcuts, along with a virtual Touch Bar at the bottom of the screen. You can use touch, Apple Pencil, and a mouse to control the Mac display on your iPad.
While the touch UI does work, it’s not intuitive. If you were hoping that Sidecar would turn the Mac into an iPad where you’ll be able to use your fingers to tap on the screen and move around, alas, this is not it. The UI elements in Mac was quite small for this to work reliably.