Chromecast Now Pairs With Phones Using Simple Ultrasonic Pulses

Google's Chromecast picked up a slew of great new features the other day. But it's also getting a new system for pairing devices which doesn't rely on sharing a Wi-Fi network—instead, it uses ultrasound. And it's more simple than it sounds.

All you have to do to enable the feature is to allow Chromecast to support nearby devices. Then, it'll send ultrasonic tones—they're too high in frequency for humans to hear—through the speakers of your TV. Nearby devices will detect the sound and sync with Chromecast, allowing them to send content to the stick. YouTube party!

It all sound weirdly simple, and that's the point: it's been designed to make using Chromecast socially way more straightforward. And the good news is that the sound won't make it through the walls—high frequency sound attenuates quickly—so you won't get trolled, either. They're clever, those Google guys. [Gigaom]