How to Use a Tablet as a Second Screen

Kees Friesland

January 4, 2017

Multi-monitor setups are now pretty common both at work and at home. Having two or more screens to sling windows across is super useful, but did you know you can use your tablet as a second screen?

For people with limited desk space or laptop warriors at hotel room desks, having another monitor can really speed up your work. It’s possible to achieve this with a USB monitor, but if you already own a tablet why spend that much money?

There’s software out there that costs a small fraction of the asking price for a USB monitor that will transform your tablet into something that does the same job.

Battle of the OSes

While all the software that works well for our purposes make use of a direct USB connection, which app you choose really does depend on what operating system you’ll use.

Android Anarchy

On Android, there are a few options. There’s Splashtop Extended Display, which only works over WiFi. I’m not a fan since network stuff has more lag and way more potential for things to go wrong.

iDisplay is, in my opinion, the best you’ll get on Android. It uses a direct wired connection and is pretty reliable and snappy. Well, it used to at least.

At the time of writing, the developers had disabled the USB connection option temporarily. Which means that the last good wired second display app is gone from the app store.

Still, I’m sure they’ll put it back eventually. Between iDisplay and Splashtop I still think iDisplay is the better choice, so that’s the app I’ll be recommending here

iOS Isolation

As usual, iOS is a tough nut to crack. While over on Android just about anyone can have a crack at the USB display thing, it took ex-Apple employees to come up with a good solution for iPads.

The good news is that Duet Display is a fast and ultra-polished program that I rely on daily to boost my productivity.

It’s perfect for me since I don’t have space for another monitor next to my 27″ main display. I also don’t need two monitors all the time.

When I’m editing videos or doing other productive work, I can use my iPad to display floating toolboxes or other programs I need to see at the same time. It also helps that Windows sees the tablet as a touch display, letting me work in an intuitive way.

There isn’t really anything else that does the job on iOS the way Duet Display does. It just doesn’t have any competition.

Using a Tablet as a Second Screen

Now it’s time to actually put these applications to use. In this section I’ll show you how to set up and use both iDisplay and Duet Display, depending on your OS.

Using iDisplay

Since iDisplay has temporarily nerfed the USB mode, these instructions will be for the wireless method.

After buying and installing iDisplay on your Android Device, head over to getidisplay.com and download the client for Mac or Windows.

Make sure you pick the right version.

Be aware that there is at least one restart involved here.

Once the client is installed open up the app on your tablet. You should see this:

The app should have auto-detected the client on your computer, as long as they are on the same WiFi network.

If for some reason it doesn’t work automatically, tap the little “plus” button. Here you can manually enter the details for the PC client. You can get the IP address and port number from the client on the PC.

Once the connection request is successfully made, you have to accept it on the computer’s side.

In this case “always allow” will do just fine.

That should be it! The tablet should now show the desktop as a second screen.

Do check out the options in the iDisplay client. You can adjust the video streaming quality and fine-tune the performance to suit your network and computer setup. There’s not much to adjust, but it’s worth having a look.

Using Duet Display

For Duet Display we have to keep our lightning-to-USB cables handy. There is (thankfully) no wireless option here.

Buy and install the app and then grab the client from duetdisplay.com

You may have to restart your PC during installation, so be ready for that and make sure everything is saved.

Once you have the client installed, using your tablet as a second screen is exceedingly simple.

First, make sure that the client on the PC side is running. Plug the iPad into the computer.

Launch the app and you should see this:

That’s all! Now you should see your second screen in all its glory.

Unlike the frugal iDisplay, Duet Display has some tasty setting for you to play with. These can make a real difference to how it all performs.

Here are the setting and what they do:

• Framerate – switch between 30 and 60 fps
• Performance – these settings affect power consumption vs picture clarity
• Resolution – how many pixels are rendered on the tablet

Which settings you choose depends on how much power you have to spare and how fast your PC CPU is. On a modern desktop plugged into the wall, I just crank it all up to max.

That is, except for the resolution. While iOS is designed to make everything usable with high pixel densities, Windows at native retina resolutions is a little hard to use.

Personally, I leave it on 1024×768. That’s big enough for a browser without being illegible.

A Tablet as a Second Screen – The Verdict

Using a tablet as a second screen is much cheaper than buying a dedicated USB monitor, but if you’re an Android user it can be a little fiddly to make it all work.

On an iPad the solution to use a tablet as a second screen is much more polished and a real pleasure to use.

Regardless of how you manage to use your tablet as a second screen, it can completely transform your productivity. Let me know in the comments if you’ve managed to make it work for you.

IMAGE CREDITS

Lead Image is Public Domain

All Screenshots by Kees Friesland