In this chapter, we learned that Google takes the efficiency of the Android platform very seriously. We also looked at the extraordinary lengths they go to in order to ensure a smooth user experience, evidencing the importance of building responsive applications.

We discussed the Android thread model and the measures that the platform may take to protect the user from apps that misbehave or are not sufficiently responsive.

Finally, we gained an overview of the general approach to building responsive apps through concurrency, and learned some of the issues faced by developers of concurrent software in general and Android applications in particular.

In the next chapter, we'll start to build responsive applications by applying the infamous AsyncTask instance to execute work in the background using pools of threads, and return progress updates and results to the main thread.