Android tablets can extend your computer screen using wireless connection software

You can turn an Android tablet into a second monitor by installing software on both your tablet and computer that mirrors or extends your display wirelessly. The tablet receives a video feed from your computer and displays it in real time, letting you drag windows, spreadsheets, or reference material onto the extra screen. This works over WiFi on the same network, so you do not need cables or special hardware.

The setup takes about 10 minutes: read an app on your tablet, read the matching desktop software on your Windows or Mac computer, connect both devices to the same WiFi network, and launch the apps. Most options let you choose whether the tablet mirrors your main screen (shows the same thing) or extends it (shows a separate workspace). The tablet becomes a true second monitor that your computer recognizes as a display.

Key Takeaways

  • You need software on both your tablet and computer—the tablet app receives video from the desktop software, so they must be the same brand or compatible pair.
  • Both devices must be on the same WiFi network; some apps also work over USB cable if your WiFi is unreliable.
  • Popular options include Spacedesk (free, Windows and Mac), Duet Display (paid, very responsive), and Microsoft Remote Desktop (free, for Microsoft accounts).
  • The tablet will drain battery faster than normal because it is displaying video constantly, so plug it in if you plan to use it for more than a few hours.
  • Lag and responsiveness depend on your WiFi speed and the app you choose; free apps tend to have more noticeable delay than paid ones.

Spacedesk: the free option that works on Windows and Mac

Spacedesk is free and works with Windows 10, Windows 11, and Mac computers. read the desktop software from spacedesk.net, install it on your computer, and restart. Then read the Spacedesk app from the Google Play Store on your tablet. Open the desktop software first, then open the tablet app—it will scan your network and show your computer as an available display. Tap your computer name to connect.

Once connected, your tablet becomes a second monitor. You can drag windows from your main screen onto the tablet screen, resize them, or use the tablet as a dedicated space for email, chat, or reference documents while you work on your main monitor. Spacedesk works over WiFi or USB cable; if your WiFi drops frequently, you can plug the tablet into your computer with a USB cable and it will use that connection instead.

Spacedesk is slower than paid alternatives—you may notice a half-second delay when moving your mouse or typing—but it is reliable for static content like spreadsheets, documents, and web pages. Video playback and fast-moving graphics will show lag. The free version has no limit on how long you can use it or how many devices you connect.

Duet Display: the paid app with minimal lag

Duet Display costs money but has much less delay than free options. A one-time purchase runs about $20 USD, though the price varies by region and may change. read the desktop app from duetdisplay.com, install it, and buy the Duet Display app from the Google Play Store on your tablet. The setup is the same as Spacedesk: open the desktop software, then open the tablet app, and select your computer from the list.

Duet Display is built for people who need responsive performance—designers, video editors, and programmers often use it because the lag is barely noticeable. It also lets you use the tablet as a touchpad or drawing tablet if your app supports it. The paid cost means fewer ads and faster updates, but it is only worth the money if you use the second monitor regularly or need the lower lag.

Microsoft Remote Desktop: for Windows computers and Microsoft accounts

If you have a Windows computer and a Microsoft account, Microsoft Remote Desktop is free and built into Windows. This app does not extend your display the way Spacedesk or Duet do; instead, it lets you control your computer remotely from the tablet, seeing your entire desktop on the tablet screen. It is useful if you want to work from the tablet itself rather than use the tablet as a second monitor.

read the Microsoft Remote Desktop app from the Google Play Store. On your Windows computer, go to Settings > System > Remote Desktop and turn on "Enable Remote Desktop." You will see a computer name—write it down. Open the Remote Desktop app on your tablet, tap the plus sign to add a device, enter your computer name, and connect. Your tablet will show your full desktop, and you can control it with touch or a connected keyboard and mouse.

Remote Desktop is slower than Duet Display because it is sending your entire desktop over the network, not just extending a second monitor. It works best for checking email, browsing files, or running light tasks on your computer from another room. It does not work with Mac computers.

WiFi connection and network setup

All wireless second-monitor apps require both your tablet and computer to be on the same WiFi network. If your computer is plugged in with ethernet and your tablet is on WiFi, they can still see each other as long as they are on the same network (most home routers handle this automatically). If you have a guest network separate from your main network, move both devices to the main network or both to the guest network—they must be on the same one.

If the tablet app cannot find your computer, restart both the desktop software and the tablet app. If that does not work, check that your WiFi is not blocking connections between devices—some public WiFi networks and corporate networks prevent devices from talking to each other. In that case, use a USB cable instead if the app supports it (Spacedesk does).

WiFi speed affects how smooth the connection is. A 5 GHz WiFi band is faster than 2.4 GHz and will give you less lag. If your tablet and computer are far from your router, move them closer or use a USB cable to eliminate WiFi as the bottleneck.

Battery drain and power management

Using your tablet as a second monitor drains the battery much faster than normal use because the screen is on constantly and the tablet is processing video from your computer. If you plan to use it for more than two or three hours, plug the tablet into a charger. Many tablets will not drain the battery at all if they are plugged in while in use.

The tablet screen will also get warm from running continuously. This is normal, but if it gets too hot to touch, unplug it and let it cool down. Most tablets have thermal protection and will slow down or disconnect if they overheat, but it is better not to push them to that point.

Troubleshooting common problems

If the tablet app cannot find your computer, make sure both are on the same WiFi network. Restart the desktop software on your computer first, then restart the tablet app. If you still cannot connect, restart your WiFi router and try again. Some routers take a minute to recognize new devices.

If the connection is very slow or laggy, move the tablet and computer closer to your WiFi router, or switch to a 5 GHz WiFi band if your router supports it. If lag is still bad, try a USB cable instead—Spacedesk and some other apps support this. A USB cable will always be faster and more stable than WiFi.

If the tablet screen goes black or the connection drops, the app may have crashed. Close the tablet app completely (swipe it away from the recent apps list), then open it again. If the desktop software crashed, restart it on your computer and reconnect from the tablet.

Frequently Asked Questions

Can I use a second monitor app with a Mac computer?

Yes, Spacedesk works with Mac. Duet Display also supports Mac. Microsoft Remote Desktop does not work with Mac computers. Check the app's system requirements before downloading to make sure it supports your Mac's operating system version.

Do I need to pay for a second monitor app?

No. Spacedesk is free and works well for most tasks. Duet Display costs about $20 USD but has much less lag. Microsoft Remote Desktop is free if you have a Windows computer and Microsoft account. Start with Spacedesk and upgrade only if you need faster performance.

Can I use this with a tablet that is not on WiFi?

No, the tablet must be connected to WiFi to receive video from your computer. Some apps like Spacedesk also support USB cable, which does not require WiFi. Check your app's documentation to see if USB is an option.

Will this work if my computer is on ethernet and my tablet is on WiFi?

Yes, as long as both are on the same network. Your router connects ethernet and WiFi devices to each other, so they can communicate. If they are on separate networks (like a guest network), move them to the same network first.

What if the app keeps disconnecting?

WiFi disconnections are usually caused by distance from the router or interference. Move the tablet and computer closer to your WiFi router, or try a USB cable if the app supports it. If the app itself is crashing, restart it and check the app store for updates.