1.3. SUMMARY

This chapter has provided a brief overview of Android, and highlighted some of its capabilities. If you have followed the sections on downloading the tools and SDK, you should now have a working system — one that is capable of developing more interesting Android applications other than the Hello World application. In the next chapter, you will learn about the concepts of activities and intents, and the very important roles they play in Android.

EXERCISES What is an AVD? What is the difference between the android:versionCode and android:versionName attributes in the AndroidManifest.xml file? What is the use of the strings.xml file? Answers to the Exercises can be found in Appendix C. WHAT YOU LEARNED IN THIS CHAPTER TOPIC KEY CONCEPTS Android OS Android is an open-source mobile operating system based on the Linux operating system. It is available to anyone who wants to adapt it to run on their own devices. Languages used for Android application development You use the Java programming language to develop Android applications. Written applications are compiled into Dalvik executables, which are then run on top of the Dalvik Virtual Machine. Android Market The Android Market hosts all the various Android applications written by third-party developers. Tools for Android Application Development Eclipse IDE, Android SDK, and the ADT Activity An activity is represented by a screen in your Android application. Each application can have zero or more activities. The Android manifest file The AndroidManifest.xml file contains detailed configuration information for your application. As your application gets more sophisticated, you will modify this file, and you will see the different information you can add to this file as you progress through the chapters.