Not the most versatile gadget, but certainly very handy.
This cleverly designed device is, in effect, a wireless HDMI cable. Using the open Miracast standard, it allows any Miracast-compatible device to sling its screen to a TV. Thus, your desktop is viewed on the big screen, and controlled by your device. It supports resolutions up to 1920x1080 and two-channel stereo and 5.1 surround, However – performance is laggy and stuttery with video, so it’s not a tool for that job. One end goes into an HDMI port, and another into USB for power.
Unlike Chromecast, it does not require a Wi-Fi network or router, big plus there. In testing with a Surface 4 Pro, it connected perfectly first time via Action Center/Connect, but the second time I connected the Surface froze during the connection process, needing a cold boot. A third attempt worked, but after disconnecting the Surface would no longer connect to the home Wi-Fi, requiring another restart. On an Android phone it worked perfectly. Using it regularly over a month, it continues to crash the Surface almost 50% of the time, so, terrific device, but it highlighted the Surface’s instability.