It's called spacedesk, and with it, I was able to quickly and easily use my tablet or my smartphone as a second monitor for my PC.

Your tablet or phone should appear in the list of available devices. Select it, and you'll see a screen share request pop up on your mobile device—tap Accept to connect.

Whichever app you try, using your iPad or Android tablet to extend your screen might boost your productivity. Or, of course, you could use the tablet on its own as a productivity-boosting tool.

Kurt "The CyberGuy" Knutsson breaks down the steps for you to be able to screen record on any of your devices, so you can show your screen to others in the future.

Duet Display lets you use any Android device as a second screen for your Mac, whether wired or wireless, giving you extra space for multitasking.

It's easy to share your screen on Skype on a computer or mobile device, as long as you have a strong enough connection to support it.

The typical solution is to connect a computer or tablet to the TV via an HDMI cable, hoping the inputs are correctly set and requiring each presenter to move to get near the cable.