Screencasting allows media from a smaller device like a smartphone to be displayed on a larger screen like a TV. It is commonly used to view videos and photos from a phone on a TV screen. Different platforms have their own screencasting features - Apple devices use AirPlay while Android devices use Smart View. To screencast, a smartphone must connect to a compatible TV or device like an Apple TV or Chromecast streaming device. The Google Home app allows screencasting from any device by mirroring the phone screen.