The source of the Google Maps Android API Utility Library is available on GitHub. The GitHub repository includes the utility classes and a demonstration application that illustrates the use of each class. To get started, follow the setup guide for Eclipse. Alternatively, the project's website includes a getting-started guide for Android Studio/Gradle and Maven. The reference documentation is also available on GitHub. Below is an overview of the utilities in the library.
This video discusses the utility library, with a focus on polyline decoding, spherical geometry, and bubble icons: