The advent of Android 3.0 introduced some significant new features, aimed in particular at tablet devices. However, there are a large number of Android tablets that run on earlier platforms and so Google produced a compatibility package so that most of these new features would run on older versions, going back as far as Android 1.6 (API level 4).
This chapter has introduced a lot of new concepts but we can conclude it with a nice and easy example showing how to install the compatibility library and how to include packages from it, so that we can take advantage of these wonderful new features on older platforms.
There is a strong chance that you have already downloaded and installed the Android Compatibility Package during a regular software update of your SDK. All the same, open the AVD manager, select Installed packages, and check that you have; it will look like this: