Google has released a design guide that will help Android app developers to create some great user interfaces. Available now, it will be enhanced and improved over the time. According to Google, it is an optional guide for the devs and company does not mean to enforce it.
The initial version of the Android design includes information related to typography, color palettes, patterns, styles and other design principles. If you are an app developer or graphic designer, it is surely worth looking and will help you include the best of Android in your app.
From Android Developers Blog:
We’re introducing Android Design: the place to learn about principles, building blocks, and patterns for creating world-class Android user interfaces. Whether you’re a UI professional or a developer playing that role, these docs show you how to make good design decisions, big and small.