Here’s How to Turn Your iPad Into a Second Laptop Screen

Although laptops are a godsend for mobile workers, they have their limitations. Their lifespan is shorter than desktop computers, especially when they're stuffed into backpacks and jostled through airport security. Travel days don't just affect you. 

Generally, processing power is reduced, storage space is often limited, and screens are usually much, much smaller. Every inch of screen real estate matters to graphic designers and video editors. Programming and writing, as well as other text-based tasks, benefit from additional space.

You're in luck if you're looking for extra pixels on the road. It doesn't have to involve spending money on a bigger laptop or trying to cram a monitor into your backpack. You might already have the answer right in front of you, in the form of your iPad.

It's actually pretty easy and inexpensive to turn that sleek Apple tablet into a second screen for your laptop (or desktop). The trick isn’t exclusive to iPad owners, either. Many of the tools listed below also work with iPhones. If you’re a Windows user, you’re also in luck, and some second-screen apps also support Android devices.

How Does It Work?

The mechanics behind this technique are actually quite simple. As we hear so often these days, “there’s an app for that”.

Apple offers an easy method for customers with recent Mac and iPad models, and those with older Apple devices, Windows computers, or Android phones and tablets can also do this. Many third-party apps are available that provide the same functionality.

All of them work similarly. It works by installing an app on both your iPad and computer (or using the one that's already there), then linking the devices through Wi-Fi or a Lightning cable to provide a seamless display across both devices.

Nevertheless, not all of these apps work equally well, or offer the same features. Here's the scoop.

Second-screen iPad Apps: An Overview

Sidecar

Do you have a Mac and iPad that were released within the past few years? Does your Mac run Catalina (macOS 10.15) or higher? Using Apple's Sidecar, you can connect your iPad to a Mac desktop or laptop, wirelessly or via a cable, and extend or mirror your display from the former to the latter.

Sidecar supports touch input, and you can also use your iPad as an input device. Sidecar is easy-to-use, slick, and straight-forward, so if your devices support it, you can use your iPad as a second screen if it's supported by your entire Apple ecosystem.

Obviously, Sidecar won't work with older devices or those that aren't made by Apple. In either of those cases, you'll need to turn to a third-party solution.

Duet

Thanks to its easy setup, lag-free wired connection, and wide range of features, Duet is arguably the most popular iPad dual-screen app.

Although the app runs at 60fps in Retina resolution, there is virtually no delay between the first and second screens. It's cross-platform (Android and Windows) and regularly updated with performance and feature updates.

It comes in two different versions (Base and Air) and a Pro version that can turn your iPad into a professional-grade drawing tablet.

If you want to connect your Windows or macOS computer to your iPad using a cable, the base version of Duet is ideal. In the Air version, you can do the same thing wirelessly, and you can use a Windows laptop as a second screen for your Mac, or vice versa.

There’s no free version of Duet, unfortunately: you’ll pay a one-off cost of $9.99 for the base version, and $19.99/year for Air.

Even so, Duet isn't perfect. On older devices, you may notice some delay if you're streaming a high-resolution display. Your laptop and iPad both have to work harder to stream the display at higher resolutions. Additionally, older versions of MacOS (10.8 or earlier) aren't supported.

Nevertheless, these are relatively minor concerns for those with somewhat-recent computers and iPads, especially considering everything Duet does well. The best way to turn your tablet into a second screen is to use this method if you're using a Windows or Android computer, or if you have an iPad or Mac that doesn't support Sidecar.

Air Display

Another popular option is Air Display 3, which works with a wired or wireless connection. Although both approaches work pretty well, using a cable will produce the least display lag. Since it works with most macOS 10.8 or later versions, it's a great choice if you've got an older MacBook.

You can also use an old Apple laptop as a second display for your Mac desktop or Mac laptop if you have both. That'll require a separate purchase: mobile and desktop clients cost $14.99 and $19.99, respectively. At least the host app is free on Mac.

However, it doesn't support the latest MacBooks with M1 chips, and it hasn't been updated for over a year. Currently, it isn't classified as abandoned, but it is heading in that direction.

If you want to use a Windows or Android device, Duet is the better choice. The last version that supported either of those (Air Display 2) is no longer supported.

Splashtop

With Splashtop XDisplay, you can use your iPad as a second screen for your Windows or Mac computer. It was once a solid free alternative that competed well with the paid alternatives. However, the developer now seems to have abandoned it. We would only recommend it to those who have older devices and can't afford the cost of a better option like Duet.

Which is the best second-screen app for iPad and iPhone? Those whose Mac and iPad meet the minimum requirements can use Apple's inbuilt Sidecar app. Others should use Duet Display. The software is reasonably priced and regularly updated, and has excellent performance that easily justifies the investment.

Once you've chosen the software you're going to use, it's time to look at the hardware.