This is a sample Home application. The Home application that users use to launch applications by default is an ordinary application itself. A user can install additional Home applications and pick which one to use as the default Home. This is a sample of such an alternative.
This is actually the source of an old incarnation of the default Home application, which may look familiar if you played with some of the older pre-1.0 SDKs.
You can find the source code for this sample in your SDK at:
<sdk>/platforms/android-<version>/samples/
