On Versions

Android Version Monuments at Google's Headquarters. From Left: Cupcake (1.5), Froyo (2.2), Gingerbread (2.3/2.4), Eclair (1.6), and Honeycomb (3.0). Image from AndroidDevelopers YouTube Channel.

Google's Android operating system for phones is definitely a moving target. During the production of this book's first version, the latest Android version available on a cutting-edge phone jumped from 1.6 to 2.2. In that time, too, phones made by HTC and Motorola became exceedingly popular, and modified versions of the Android interface, HTC's "Sense" and Motorola's various "Blur" versions, have become the de facto standard for what a new Android buyer sees. Different phones have seen updates at very different paces, with a small group of phone owners still loaded with Android 1.6 and wondering if they'll ever see a ping from out of the sky about a new version ready for downloading.

This guide was written with the newest version of Android in mind, running on Google's own Nexus One phone, though that changed from Android 2.1 to 2.2 somewhere in the middle of the text. I've since updated it to include parts of Android 2.3, and added a chapter on Android 3.0, a tablet-only version. The whole book was also conceived, at first, as focusing on a "stock," unmodified Android interface, though the significant differences in the HTC and Motorola home screens, and particular apps, are covered. In short, we tried to look forward and diversify throughout, but especially where a difference might matter.

On Hardware

As noted above, this book was written primarily using a Nexus One, which is fairly representative of today's Android phones, as far as that goes. It features a trackball, which does not appear on all phones, and lacks a physical, QWERTY-style keyboard, unlike the popular Droid models. The camera offers a 5 megapixel capture and has a flash, but can't shoot 720p video or let the shooter alter the focus with a touch.

In other words, your hardware will likely vary from any other Android owner's phone, but Android was meant to incorporate many designs and features without needing an entirely new system.

On Rooting

Android is based on the Linux operating system that powers huge server installations and individual computers alike. Inevitably, that means that computer and programming enthusiasts have sought to get deeper access to Android's internals--to become a "root" user--to both add creative new features, and fix those things that irk them about their phones.

This guide was not written with "rooted" phones at its core--but rooting isn't something to look down on, either. Coders and communities like those behind the CyanogenMOD project have unleashed nifty fixes and upgrades on modern phones, and given the owners of phones left behind by their makers and carriers a new lease on life.

In a few cases, the answer to "Why can't I fix this?" may lie in rooting your Android phone--but be cautious, and do lots of research, if you choose to go that route. Altering your phone's core firmware will almost certainly void your warranty, and missing a step or using the wrong files can result in a phone that's "bricked," and can no longer function.