Back on Feb. 3rd we reported that the Google cast SDK was being pushed out by Google as promised, and along with it they updated that Google Play Services to version 4.2, which would add in a host of new APIs as well as more Chromecast support for apps, and the ease of use for developers to make their already existing apps easier to stream to the TV. As of now the Google Play Services 4.2 update is live for everyone, and the rollouts are just beginning so you may start to see that Google Play Services is updating on your devices as you're reading this, or it may take a day or two. Besides the new APIs, which are really probably not that interesting or important to most consumers, this new update should make it so we start to see a flood of new Chromecast apps hitting the Play Store soon. Many of us thought they would be ready back when Google opened up the SDK itself, because developers could take the SDK and readily apply it to their app and things should have been good to go. This wasn't the case however as Google had stated that they were waiting until the 4.2 version of Google Play Services update was ready to go live for the world, before they would allow these new Chromecast apps or existing developer apps with newly added Chromecast support to go live.
The new Google Drive API has also been added in with this Google Play Services update, which allows users to easily save an offline copy of any files from Drive supported apps, then sync it to Drive once an internet connection becomes available again. This makes things so much easier for many users who utilize Drive as their main cloud storage option for all types of files. Lastly, the update includes the Client API which helps out developers. This is nothing that users should be concerning themselves with simply because they won't really see much of a change from this on the their end. Basically what it does is allow developers to make connections to all Google's services within their apps that much easier, giving developers a way to work with and have all their apps connected with a more seamless integration with all of the Google Play Services, like Google play Games, Google+, and Gmail etc. Developers should love the addition of the Client API as it provides one connection to cover every service, as opposed to a completely different API for each one. This ultimately makes things less cluttered on the developer end of things and should make it quicker to work the API as well.