Google is planning to add Android screen mirroring to Chromecast "very soon", allowing users to stream their phone screen to a television set.
It was found in Android 4.4.1 code by Koushik Dutta, co-founder of Cyanogenmod. It's not clear when Google plans to release the feature, but small code snippets are usually an indication of features to come.
Currently Chromecast, available on Google Play for $35, allows mirroring from a Chrome browser tab on laptop or desktop to a television, but so far on Android devices it's been locked down to supported apps like Netflix, HBO Go, and others.
Without the help of Google, Dutta and his team are working on a third-party solution to stream your Android phone's screen through the Cyanogenmod software, a customer Android firmware. Google limitations may be slowing it down, however.
"Unfortunately that API is not available to anyone but Google and the OEM," Dutta said. "Similar solutions to different hardware can't be built (Apple TV, etc)."
Until Chromecast support is released soon, the only way for Android users to stream their phone's screen to a television is through Miracast, a peer-to-peer wireless screencast standard formed via Wi-Fi Direct connections in a manner similar to Bluetooth. There are several dongles on the market, starting as low as $25. Android support was added in 2012.
On the other side of the competition, iOS allows users to stream their iPhone or iPad screen over AirPlay to an Apple TV.
A mobile screen streaming feature on Android would put the platform on a par with iOS in this regard.
Chromecast, measuring just 2 inches in length, runs a simplified version of Chrome OS and is designed to be completely cross-platform, working with Chrome, Windows, Mac, Android, iPad and iPhone. It connects to your TV via HDMI to supply the video and audio, and will connect to your home Wi-Fi network to pick up that content from its source online.