Google has rolled out a software update for the Chromecast media streamer that lets you connect your phone or tablet to a Chromecast even if the devices aren’t on the same WiFi network.
The new guest mode feature lets you send content from your phone to a Chromecast at a friend’s house without having to share a WiFi password.
You’ll need the latest Chromecast app to turn on guest mode in the device settings menu. Once you’ve done that the Chromecast will be able to connect to any device in the same room simply by sending an audio tone (that’s inaudible to humans… or at least adults) to share a PIN code with your device. If that doesn’t work a guest user can just enter the PIN displayed on the home screen of a Chromecast.
From there, the guest can use their phone or tablet to find content from YouTube, Hulu Plus, Netflix, HBO Go, or dozens of other services and send it the TV that has the Chromecast connected. Note that you won’t be able to send local videos or other content from your phone to a Chromecast unless the devices are connected to the same network, so apps such as LocalCast will not work.
Guest mode requires Android 4.3 or later and doesn’t work with iOS devices or PCs.
Google first unveiled guest mode in June, but the feature is just now rolling out to users.
via Android Police
I think you have this backwards. A friend comes to your house and sends commands to your Chromecast on your wifi network to play something without you having to share your wifi password with your friend.
All your friend does is relay a link to the Chromcast and it still goes over your own established wifi to get the video and play it.
If you take it to someone else’s house you will still need to setup the wifi on the Chromecast to link to their network.
The (older) linked article says “Then you can find media you want to play while your phone is connected to your cellular network”, so I suppose it is using a server out on the internet to relay commands/instructions. This would also explain why casting from phone to screen wouldn’t work….
I wonder how this works. It must pass the url and control information back to the chromecast with audio as well? Or is it bluetooth or something?