Duet Display Alternatives for Mac: Sidecar, Luna and More

Duet Display turns an iPad, iPhone, Android tablet or another computer into an extra screen for your Mac. It's still actively updated, it works across Apple, Windows and Android devices, and its paid tiers add remote desktop and an Apple Pencil drawing mode.

It is also a subscription. On the US App Store, Duet's plans run from Duet Starter at $3.99 a month or $39.99 a year to Duet Pro at $7.99 a month or $79.99 a year, with Duet Air at $5.99 a month or $49.99 a year in between. If you just want your iPad next to your MacBook as a second display, you may not need to pay anything at all. Here are the alternatives worth trying, starting with the ones already on your Mac.

Quick Verdict

• Best for most people with an iPad: Sidecar, built into macOS and iPadOS. Free, wired or wireless, with Apple Pencil support.
• Best for using another Mac as a screen: AirPlay to Mac, also built in. Turn an old MacBook or iMac into a wireless second display.
• Best one-time purchase: Luna Display, a $89.99 hardware dongle that works with older Macs, Windows PCs and headless Mac minis that Sidecar can't handle.
• Best for Android tablets and other devices: Deskreen, a free, open source app that streams your screen to any device with a web browser.
• Best for artists: Astropad Studio, which turns an iPad and Apple Pencil into a professional drawing tablet for your Mac or PC.
• Stay with Duet if you mix Windows, Android and Apple devices, or want one subscription for second screens, remote access and drawing.

Feature Comparison

Sidecar

Sidecar is the alternative most Duet users should try first, because they already have it. It lets an iPad extend or mirror your Mac's desktop. Drag a window to the iPad, or hover over a window's full-screen button and choose to move it there.

It works wirelessly when the devices are within 10 meters (30 feet) of each other, or over USB, which also keeps the iPad charged. A sidebar on the iPad gives you Command, Option, Control and Shift keys, undo, the Dock and an onscreen keyboard. You can show a virtual Touch Bar and use Apple Pencil to point, click and draw in Mac apps. Apple says that with macOS 27 and iPadOS 27, Sidecar adds much broader touch support for working with Mac windows and menus on the iPad; earlier versions only support a few gestures, such as two-finger scrolling.

The limits are compatibility and devices. Sidecar needs macOS Catalina or later on a MacBook Air from 2018 or later, a Retina 5K iMac from late 2015, or another Mac from 2016 or later, plus an iPad Pro, iPad (6th generation or later), iPad mini (5th generation or later) or iPad Air (3rd generation or later). Both must be signed in to the same Apple Account with two-factor authentication. It only works between a Mac and an iPad: no iPhone, Android or Windows.

Choose Sidecar if you have a supported Mac and iPad. It's free, and for many people it's all they need.

AirPlay to Mac

If your spare screen is another Mac rather than an iPad, macOS can already use it as a display. Since macOS Monterey, supported Macs can act as an AirPlay Receiver. Turn it on in System Settings > General > AirDrop & Handoff on the Mac you want to use as a screen. Then, on your main Mac, choose it from Screen Mirroring in Control Center and switch from mirroring to Use As Separate Display.

That's a good use for an old MacBook or an iMac sitting next to your laptop, and it costs nothing. It's wireless only, so picture quality and responsiveness depend on your network. Older Macs may not support AirPlay Receiver at all, and Macs managed by an employer may have it turned off.

Choose AirPlay to Mac if you have a recent spare Mac and only need an occasional second screen.

Luna Display

Luna Display is Astropad's answer to Duet, with one big difference: you buy it once. It's a small dongle (USB-C or HDMI) that plugs into your main computer, paired with free apps on both devices, and connects over your Wi-Fi network or a USB cable. Astropad lists it at $89.99.

It has three modes. Computer to iPad turns an iPad into a second display for a Mac or PC. Computer to Mac uses another Mac as the display, and Astropad says it works with older Mac models too, which makes it a way to reuse an iMac that's too old for AirPlay to Mac. Headless Mode lets a Mac mini or Mac Pro use an iPad or Mac as its main screen, which is handy for travel. The iPad app is rated 4.8 from about 4,000 ratings on the US App Store and was last updated in September 2026.

The downsides: it's hardware you have to carry and can lose, it uses a port on your computer, and Astropad notes it doesn't work through adapters. On a Mac and iPad that already support Sidecar, the gain is smaller.

Choose Luna Display if you want to avoid a subscription and your devices are too old for Sidecar or AirPlay, or if you need a screen for a headless Mac mini.

Deskreen

Deskreen takes a different approach: it streams your Mac's screen to any device with a web browser over Wi-Fi. There's no app to install on the second device, so an Android tablet, a Kindle Fire, an old Windows laptop or a phone can all work. It's open source (on GitHub) and still maintained; version 3.2.16 shipped in July 2026 with builds for Apple silicon and Intel Macs.

By default, Deskreen mirrors your whole screen or a single app window. To use the other device as a true extended display, you need a virtual display on your Mac for Deskreen to stream. BetterDisplay can create one. Deskreen also has a flip mode for using a tablet as a teleprompter, and it encrypts the stream end to end.

The free Community edition connects one device. Deskreen Pro costs $24.99 a year and adds up to five devices, the teleprompter flip mode, advanced video controls, trusted devices and more reliable reconnects. Keep expectations realistic: it's a video stream in a browser, so it suits reference material, chat windows and dashboards better than fast-moving work. It sends only the picture, so you keep working with your Mac's keyboard and trackpad.

Choose Deskreen if your spare screen isn't an iPad or a Mac, or you want a free option that works with almost anything.

Astropad Studio

Astropad Studio is for one specific Duet use: drawing. Duet Pro turns an iPad into a graphics tablet; Astropad Studio is built only for that job. It mirrors your Mac or PC screen to the iPad so you can draw with Apple Pencil in Photoshop, Affinity, Clip Studio Paint, Krita and other desktop apps.

The extras are aimed at artists: custom finger and Apple Pencil gestures, a shortcut sidebar that changes with the app you're using, quick keys, custom pressure curves, pressure smoothing and hover support on 2022 iPad Pros. It connects over USB, Wi-Fi or peer-to-peer networking. After a 14-day free trial, it costs $99.99 a year, more than Duet Pro on the App Store.

It isn't a general second-screen app. If you just want more room for windows, use Sidecar or Luna Display instead. If you draw for a living, see our Procreate alternatives for Mac for the painting apps to pair it with.

Choose Astropad Studio if you use your iPad as a pen display every day and want more control than Sidecar's Apple Pencil support.

What About Universal Control and spacedesk?

Universal Control often comes up in these searches, but it doesn't make your iPad a display. It lets your Mac's keyboard and trackpad control an iPad (or another Mac) that keeps running its own apps. That's useful, but it isn't a second screen for your Mac's windows.

spacedesk is a popular free option on Windows, but its host software only runs on Windows; on a Mac you can only use it as the receiving screen. Splashtop Wired XDisplay was left out because its Mac app supports only macOS 10.13 and earlier.

Which Should You Choose?

• Choose Sidecar if you have an iPad and a Mac from roughly 2016 or later. Try it before paying for anything.
• Choose AirPlay to Mac if your spare screen is a recent Mac.
• Choose Luna Display if you want a one-time purchase, have older hardware, or run a headless Mac mini.
• Choose Deskreen if your extra screen is an Android tablet, a Windows laptop or anything else with a browser.
• Choose Astropad Studio if you mainly want to draw on your iPad in desktop apps.
• Stay with Duet Display if you need iPhone, Android and Windows support in one app, or also use its remote desktop features.

Final Verdict

For most Mac users with an iPad, Sidecar makes Duet Display unnecessary: it's free, fast over USB, and gets better touch support in macOS 27 and iPadOS 27. AirPlay to Mac does the same for a spare Mac. Luna Display is the best paid alternative if you'd rather buy once than subscribe, especially for older Macs and headless setups, and Deskreen covers almost any other device for free. Astropad Studio is the pick for artists. Duet still earns its subscription when your devices span Apple, Windows and Android, but try the built-in options first.

Catch these apps on sale: many paid Mac apps and accessories, including second-screen tools, run discounts at least once a year, most often around Black Friday. Subscribe to the Apps.Deals newsletter to hear when the deals arrive.

Note: Features and prices are current as of November 2026. Prices may vary by region; check each developer's site before buying.