My book focuses on the Java language and foundational APIs (such as regular expressions and collections) that are part of Java SE and Android -- I only cover APIs that are part of both platforms, which restricts me to Java 1.5 because Android APIs are based on Java version 5. I'll follow this same practice with the six PDF-based chapters that I'm writing to supplement my book, and which will be freely available to download from my website over the next few months.
Despite similarity of language features and many APIs, there are significant differences between Java SE and Android development. For example, the concepts of application are very different in Java SE and Android. For example, a Java SE application has a class with a public static void main(String args) method. In contrast, an Android application consists of some combination of activities, services, broadcast receivers, and content providers -- there is no class with a main() method because there is no single entry point. Any component of the Android application can be started when requested by another application and when the component's application allows other applications to start it.
Another area of difference is threading. In Java SE, you would typically work with the low-level Threading API or the concurrency utilities (or perhaps some combination of the two). In Android, you typically work with special classes such as Looper, MessageQueue, and Handler.