How to use your iPad as a second monitor for your Windows computer

To use an iPad as a second screen on a Windows 10 computer, you'll need to use a third-party app like SplashTop.

How to screen mirror your Android to a TV or computer, even without a Chromecast

To mirror your Android's screen, you'll need a Chromecast, a compatible TV, or a third-party app like Tenorshare Phone Mirror ...