Astropad gave us our first taste of how well the iPad can function as an extension of your Mac. The company's Luna Display takes the idea to its logical conclusion, letting the iPad serve as an external monitor. Leveraging a physical connection to your Mac and proprietary Liquid technology, it provides lag-free, graphics card-driven performance wirelessly. It can also do something no other external setup can: let you manipulate the OS using just your fingers, and draw right on the screen with the Apple Pencil. Available for Mini DisplayPort or USB-C and compatible with most modern Macs and iPads.