Can the regular iPad models be used as an external display for a Mac or PC? Which regular iPad models support Sidecar?

Originally, the iPad models were not designed to be used as a second display for a Mac or PC and Apple did not provide this capability out of the box.

However, clever programmers wrote third-party software to add this capability and it became quite possible to use any iPad running iOS 7 or later as an external display (only the original iPad is not capable of running iOS 7 or later). Early versions of software only connected via Wi-Fi and often were slow and laggy, but later software made it possible to connect from a computer directly to the iPad via its 30-pin or Lightning port and worked very well. Of course, Wi-Fi networks can be much faster now, too.

iPad Sidecar Support (iOS 13 & Later/macOS Catalina & Later)

As a new feature introduced with iOS 13 (iPadOS), in conjunction with macOS Catalina (10.15), Apple knocked off the functionality of these independent apps and integrated it with the company's operating systems. This functionality remains in subsequent and current versions of the iPadOS, too.

This feature now is called "Sidecar" and among regular iPad models, it allows the iPad (6th Gen), iPad (7th Gen), iPad (8th Gen), and iPad (9th Gen) models to be used as a second display for a Mac:

Sidecar-Compatible iPad Models	Model No
iPad 9.7" 6th Gen (Wi-Fi Only)	A1893
iPad 9.7" 6th Gen (Wi-Fi/Cellular)	A1954
iPad 10.2" 7th Gen (Wi-Fi Only)	A2197
iPad 10.2" 7th Gen (Wi-Fi/Cellular, US/CA)	A2200
iPad 10.2" 7th Gen (Wi-Fi/Cellular, Global)	A2198
iPad 10.2" 7th Gen (Wi-Fi/Cellular, China)	A2199
iPad 10.2" 8th Gen (Wi-Fi Only)	A2270
iPad 10.2" 8th Gen (Wi-Fi/Cellular, US/CA)	A2428
iPad 10.2" 8th Gen (Wi-Fi/Cellular, Global)	A2429
iPad 10.2" 8th Gen (Wi-Fi/Cellular, China)	A2430
iPad 10.2" 9th Gen (Wi-Fi Only)	A2602
iPad 10.2" 9th Gen (Wi-Fi/Cellular, US/CA)	A2603
iPad 10.2" 9th Gen (Wi-Fi/Cellular, Global)	A2604
iPad 10.2" 9th Gen (Wi-Fi/Cellular, China)	A2605

Some iPad mini, iPad Air, and iPad Pro models also are compatible.

iPad External Display Software for Mac & Windows

If you have compatible hardware, you might as well use Sidecar these days, but if you have an older iPad (and/or an older Mac or a Windows PC), one of these pioneering apps may come in handy.

Four apps worth considering to use your iPad as a second display with your Mac or PC include Duet Display, AirDisplay, iDisplay, and Splashtop XDisplay.

All four apps work in effectively the same way with one app for the iPad and a companion app installed on the "paired" computer.

Duet Display

Reportedly designed by former Apple engineers, Duet Display widely is considered to be the leader for this type of app. After being disappointed by an earlier app from another company, EveryiPad.com discovered this app and found it to work well. It only connects via 30-pin, Lightning, or USB-C and does not offer a Wi-Fi connected solution.

The current version of Duet Display is compatible with Macs running OS X 10.9 (Mavericks) or higher and Windows 7 and higher as well as all iPad models running iOS 10 or later.

iDisplay

Early versions of iDisplay only connected an iPad to a computer via Wi-Fi, but the current version supports both direct cable connection and Wi-Fi options.

The current version of iDisplay is compatible with OS X 10.9 or higher and Windows XP or higher and all iPad models running iOS 8 or later.

AirDisplay

AirDisplay connects an iPad to a Mac via Wi-Fi. It does not support direct cable connections nor does the current version support Windows.

AirDisplay is compatible with Macs running OS X 10.8 or higher and iPad models running iOS 7 or later.

Splashtop XDisplay

Splashtop XDisplay is a more recent entry to the game, but from a developer with extensive experience developing iOS business apps.

Splashtop XDisplay is compatible with Macs running OS X 10.9 or higher and Windows 7 or higher and all iPad models running iOS 7 or higher.

Of these four apps, EveryiPad.com would suggest Duet Display because it is a well designed app and one that we have used personally, although it is the most expensive.

iDisplay is well worth considering particularly if you have an older Windows PC running Windows XP and AirDisplay is well worth considering if you have a Mac running OS X 10.8 (Mountain Lion) and a strong Wi-Fi connection. Splashtop XDisplay has a more barebones interface, but it is cheap.

Buy a Portable Monitor Instead

Photo Credit: ASUS, Inc. (ASUS Notebook & MB169+ USB Portable Monitor)

If you like the idea of using an iPad as a second compact display for a Mac or Windows PC, you might prefer to instead purchase a travel monitor like the Mac compatible Asus MB169+ USB Portable Monitor.

This portable monitor is physically larger than an iPad, and doesn't work as a tablet computer, but it doesn't weigh much more, has a greater viewable area, and costs much less.

iPad as Second Display Summary

Ultimately, the iPad is too expensive just to use as a second display for a Mac or Windows PC. However, if you have an iPad that you carry with you in addition to a notebook computer, using the iPad both as a tablet and as a second display can be a convenient way to save space when traveling.

Using an older iPad as a second display also is a good way to repurpose it at home if you have subsequently purchased a newer iPad and you would like to add another smaller external monitor to an existing multi-display Mac or PC setup (or you do not currently have sufficient funds to purchase an external monitor for your Mac or Windows PC).

If you just want a compact second display to carry on the road with a Mac or Windows notebook, an Asus USB Portable Monitor might be even better for you.