The moment the rollout is complete, one will be able to download the Google Play services SDK using the SDK Manager, as well as begin on the new APIs. With the aforementioned Google Analytics and Google Tag Manager, this release turns them into “first class citizens” in Google Play services, and those who have used the API before would find it to be rather similar to previous versions.
Google Analytics enables one to get a detailed breakdown on how your app is being used by your users, including the functionality that is used most frequently, as well as the activity that triggers users to convert from an advertised version of an app to paid one. [Press Release]