A worthwhile read, but it's already out of date (as it itself warns). Some of the things I tried didn't work because of deprecation. Easy to follow though. Glad I read it.

If you've been developing Flex, chances are good you've heard a little something about Apollo. This book provides a great overview -- I came away with an excellent understanding of Apollo's "whats" and "hows" within a half hour of picking up this book.

This book is a good overview of what is involved building applications that use the Adobe Flex Framework with the cross-platform desktop runtime, Apollo. The book assumes that the reader has experience creating Flash-based applications using Flex and ActionScript 3.0, and that you want to leverage that experience and move on to deploying applications with Apollo. It is a good basic introduction to get you started, not an in-depth guide by any means.

1. Introduction to Apollo - Explains the difference between the Apollo runtime and Apollo applications, the capabilities and the limits of Apollo, and the basic structure of Apollo applications.
A Short History of Web Applications
Problems with Delivering Applications Via the Browser
Introducing the Apollo Runtime
Primary Apollo Technologies

2. Getting Started with Apollo Development - Discusses how to initialize your development environment and begin building Apollo applications that use the Flex framework. It shows you where to get the resources necessary for Apollo application development and goes through the details of writing and deploying a Hello World application.
Installing the Apollo Alpha 1 Runtime
What You Need in Order to Develop Apollo Applications
Building a Sample Apollo Application
Next Steps

3. Using HTML Within Flex-Based Apollo Applications - Describes how Apollo gives developers a new means of integrating HTML rendering into their desktop applications. Included are some basic applications that demonstrate how to write HTML-enabled Apollo applications.
HTML Support in Apollo
Using the Flex HTML Component
Using the HTMLControl Class
Script Bridging: Communicating Between ActionScript and JavaScript

4. Using the File System API - Discusses the various aspects of the Apollo file I/O API that enables applications to have a great deal of freedom in dealing with the files and directories of the user's computer. There are quite a few code snippets in this chapter that serve as simple examples.
Security Model
Accessing Files and Directories
Asynchronous and Synchronous Versions of Methods
Reading Directory Contents
Getting File Information
Copying and Moving Files and Directories
Creating Files and Directories
Deleting Files and Directories
Reading and Writing Files

5. Apollo Mini-Cookbook - O'Reilly, famous for its cookbook series, provides a mini cookbook of solutions to common problems in Apollo applications and includes working MXML code. Recipes include those for reading and writing text from a string, encoding data into PNG or JPEG format and writing it to the file system, and working with the Windowing API.
Working with the File System
Working with HTML
Using the Windowing API

Apollo Packages and Classes
Apollo Command-Line Tools

Actually you can find this book freely available online. Just type "Adobe Apollo for Flex developers pocket guide" without the quotes into Google. It should be the top address.

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Adobe's Apollo, in the just-released alpha runtime, is the latest entry in the world of "Rich Internet Application" frameworks.

Advocates of RIA frameworks often weaken their arguments for the Web-aware desktop by disparaging browser-based applications beyond the credible. The universe of browser-based applications continues to expand for very good reasons.

Give the authors, all members of the Apollo product team, plenty of credit for their relaxed approach in this guide. Their introductory chapter sticks to a positive case for their approach rather than attack the weaknesses of current Web apps.

Chapters 2 and 3 outline setting up the environment and move quickly to working with the HTML rendering engine. Following chapters deal with the security model and the file system and windowing APIs.

The weakness of the book is that it is Flex-centric in its "hello world" examples. The book reflects the state of the Apollo alpha. The book itself is clear and easy to follow.
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