We've already seen how doubleTwist makes it easy to listen to your music and watch video over AirPlay devices from your Android phone or tablet. Today the company has decided to release an update that allows rooted users to stream Google Play Music to AirPlay devices as well. They also wrote a blog post to tell us how they are making it work.
Google Play Music uses a whitelist of approved applications that can use a streaming API. It's the same API used for Chromecast, and most recently Sonos. doubleTwist isn't on that white list — and we don't know why — so they devised a root-only app that can edit it to add themselves.
You install the $2.99 Magic Play app (see the Google Play link at the top of the page), launch Google Play Music, tap the cast button which now asks for root permissions. Once granted, force close the Google Play Music app and upon restart you should see AirPlay devices in your list.
We can't help but think circumventing Google's approval process is not going to please Google — or the content providers — but presumably someone at doubleTwist has considered this. It will be interesting to see how it plays out, and what Google's reaction will be.