Chromecast's big selling point is its convenient interactivity with your smartphone, and its $35 price tag. Google's latest update to the hardware makes it even easier to share videos in your living room.
The update lets the Chromecast dongle communicate with smartphones using ultrasonic frequencies. If that sounds confusing, here's how it will actually work.
You're having friends over. The Netflix movie is over, but an impromptu "have you seen this?" YouTube party starts. Chromecast has always let you collaboratively populate YouTube playlists. The app required both smartphones to be on the same Wi-Fi network, but not anymore.
The Chromecast app emits an ultrasonic noise that identifies it as being a part of your network, and then your friend has instant access to your YouTube playlist.
Ultrasonic sound identification just made watching YouTube videos on Chromecast a whole lot easier.