In-app Billing is expanding again today, making it even more powerful and flexible so you can continue to build successful applications. Version 3 introduces the following new features:
An improved design that makes applications simpler to write, debug and maintain. Integrations that previously required several hundred lines of code can now be implemented in as few as 50.
More robust architecture resulting in fewer lost transactions.
Local caching for faster API calls.
Long-anticipated functionality such as the ability to consume managed purchases and query for product information.
In-app Billing version 3 is available to any application that uses in-app items (support for subscriptions is coming shortly). It is supported by Android 2.2+ devices running the latest version of the Google Play store (over 90% of active devices).Google Android Announces In-App Billing Version 3 [android-developers.blogspot.co.uk]