Android is everywhere. In mid-2016, Android runs on 65 percent of all smartphones in the United States, on 75 percent of all smartphones in EU5 countries, and on 77 percent of all smartphones in China.1 In a study that spans the Americas, Europe, Asia, and the Middle East, GlobalWebIndex reports that “Android is the most favored OS when it comes to tablets, being used by almost a fifth of internet users and leading iPad by 5 points.”2 More than 2.2 million apps are available for download at the Google Play store.3 And 9 million developers write code using Java, the language that powers Android devices.4
If you read this book in a public place (on a commuter train, at the beach, or on the dance floor at the Coyote Ugly saloon, for example), you can read proudly, with a chip on your shoulder and with your head held high. Android is hot stuff, and you're cool because you're reading about it.
You can attack this book in either of two ways: Go from cover to cover or poke around from one chapter to another. You can even do both (start at the beginning, and then jump to a section that particularly interests you). This book was designed so that the basic topics come first, and the more-involved topics follow them. But you may already be comfortable with some basics, or you may have specific goals that don't require you to know about certain topics.
In general, my advice is this: