Comparison · 2 min read · facts checked
Universal Control shares one keyboard and mouse between nearby Macs and iPads, but each device keeps its own screen. Sidecar uses an iPad as a display for a Mac. Screen Sharing shows another Mac's whole screen. To open one app window from another Mac as a window of its own, use an app such as Wormhole.
Apple ships three features with "another device" in their description, and they are easy to mix up: one moves your pointer, one moves your display, one shows a screen. None of them brings a single app window from one Mac to another. Every fact about Apple's features below comes from Apple's own support pages, checked on 5 November 2026.
What does each one actually do?
| Universal Control | Sidecar | Screen Sharing | Wormhole | |
|---|---|---|---|---|
| What it does | Your Mac's keyboard, mouse or trackpad controls up to two other nearby Macs or iPads | An iPad extends or mirrors your Mac's desktop | Shows and controls another Mac's screen in a window | Opens one window from another Mac as a window of its own here |
| Do you see the other Mac's apps on this screen? | No: each device shows its own screen and apps | No: the iPad shows this Mac's desktop | Yes, the whole screen; with several displays, you pick one | Yes, one window at a time, each in its own window; "Whole screen" is in the picker too |
| Devices | Mac with Mac or iPad | Mac with iPad | Mac with Mac | Mac with Mac |
| Requirements | macOS Monterey 12.4 or later, iPadOS 15.4 or later | macOS Catalina or later, iPadOS 13 or later | Screen Sharing turned on on the Mac you connect to | macOS 14 Sonoma or later, Apple silicon or Intel, the app on both Macs |
| Apple Account | The same one on every device, with two-factor authentication | The same one on both devices, with two-factor authentication | Not required: a user name and password, or connect by Apple Account | Not used: pair once with a six-digit code on both screens |
| Distance | Within 10 meters (30 feet), Bluetooth, Wi-Fi and Handoff on | Within 10 meters (30 feet) wirelessly, or over USB | On your network, or by hostname | On your network, or by IP address or hostname (over Tailscale, for example) |
| Comes with macOS | Yes | Yes | Yes | No, a download (pricing) |
Universal Control vs Screen Sharing
Universal Control is a shared keyboard, not a shared screen. Apple's page is explicit that each device keeps showing its own screen and apps; your pointer just slides across to the Mac or iPad beside you. It needs that other device to be physically next to you, within about 10 meters.
Screen Sharing is the opposite: you see the other Mac's screen, inside one window on yours, and you can control it. It works for a Mac in another room or with no keyboard of its own, and it shows you everything on that screen at once.
Sidecar vs Universal Control
Both pair a Mac with an iPad, which is why they get confused. Sidecar makes the iPad a second display for your Mac: the Mac's own windows move onto it. Universal Control leaves the iPad running iPadOS and lets your Mac's keyboard and trackpad drive it. Apple's Sidecar page describes an iPad as the display; it does not describe a Mac as a display for another Mac.
How do I share one window between Macs?
None of the three does it. Screen Sharing comes closest, but you get the whole screen in one window. Wormhole lists the other Mac's windows and opens the one you pick as a window of its own on this Mac, with its own Dock icon and ⌘Tab entry; you can open several, and click and type into each. It needs the app on both Macs. How to set it up, and what it does not do yet.
For a deeper look at each option for a second Mac, see four ways to use another Mac's apps, and Wormhole vs macOS Screen Sharing.
Related
- Jump Desktop vs Wormhole: whole screen or one window?
- Wormhole vs Beam: one Mac's window on another
- Wormhole vs macOS Screen Sharing