Earlier today Google flipped a switch enabling the screen casting feature it unveiled at Google I/O. If you have one of the supported devices, you don't have to do a thing to try it out. Just fire up Quick Settings and hit the screen cast icon. But if this isn't discoverable enough, Google has also updated the Chromecast app to bring more attention to the feature.
A Cast Screen option is now available in the navigation sidebar. Clicking it will provide a brief explanation of the feature and walk you through setting it up.
The app also displays which Chromecasts are available in your home to cast to and which device is currently casting to what.
Everything needed to run Backdrop is included in this APK. There are several thousand lines of code,
The APK is signed by Google and upgrades your existing app. The cryptographic signature guarantees that the file is safe to install and was not tampered with in any way. Rather than wait for Google to push this download to your devices, which can take days, download and install it just like any other APK.