Universal Control is coming in macOS Monterey, but you can use any device as a second monitor right now with the right software or accessories.

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.

If you have an Android tablet, you can transform it into a portable display for your Windows PC. This can be useful when you need extra screen space or want to present content on your PC to ...

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.

The Lenovo Yoga Pad Pro is something of an unusual Android tablet, featuring an HDMI input to use it as a monitor ...