Earlier today, Google Play Services version 21.21.12 started rolling out to users. The last beta release was version 21.18.14, so we're expecting there to be a bunch of changes under-the-hood. While we haven't spotted many interested changes from a cursory glance, we did find further evidence that Google will soon let users stream apps from their phone to a connected Chromebook.

An APK teardown can often predict features that may arrive in a future update of an application, but it is possible that any of the features we mention here may not make it in a future release. This is because these features are currently unimplemented in the live build and may be pulled at any time by the developers in a future build.

The following strings explicitly say that you'll be able to streams apps to your Chromebook, however they don't provide any details on how the feature works:

        <string name="apps_stream_enabled_description">Stream apps to your Chromebook</string>
<string name="apps_stream_enabled_title">Apps</string>
    

The feature isn't available yet on my Pixel 4 running the latest Google Play Services release. However, we've been expecting this feature to land thanks to Chromium code hints back in February. At that time, we learned that Google is preparing to extend Chrome OS' new Phone Hub feature with app streaming. In the future, Chromebooks will add a System Web App (SWA) that syncs video and bidirectional data over WebRTC. It's believed the feature will be exclusive to Pixel phones, though we haven't found any information about device availability from a preliminary look at the latest Play Services release.

One feature that has been enabled in this release is a toggle to disable Cast device discovery. Toggling this will prevent nearby Cast devices from being discovered. Google Play Services can discover Cast devices that are connected to the network, but until now, you couldn't turn this off.

We'll continue digging into this release for more features.