If you have an old Android tablet, or a new foldable phone, why not turn it into a portable monitor? Here's how I've done it.

spacedesk is a free app that lets you use an Android tablet as a second display for your Windows PC. Learn how to set up and use it.

Need an extra monitor but don't want to buy one? Your phone or tablet is already the perfect second screen—you just need the right app to make the most out of it.