Book excerpt: The success of the first edition of this book motivated me to write the second one. The first edition was written with the objective to put a big picture of Oracle Application Express in front of the audience, and revolved around the sample application to demonstrate the practical aspect of the technology. The previous edition emphasized on the HOW area and didn't deeply elaborate the WHY part. After getting valuable feedback from the respected audience, I spent ample time to revise my work with some more useful stuff. This book is written keeping in view those suggestions. Focusing on the current Oracle Application Express version (4.2), it contains the following new enhancements to show how to develop web applications with the help of this unique declarative rapid application development (RAD) tool. - Mobile web application development - Utilization of new themes and grid layouts in desktop and mobile web applications - A new chapter to elaborate different areas of the technology - Hands-on, step-by-step instructions with thorough explanations - Improved user-friendly book layout You'll create two flavors of a web application in this book: desktop and mobile. The desktop version teaches you many techniques that will aid you in your own development tasks. Once you complete the application, and fully understand the provided instructions, you'll be able to develop Internet facing applications as well as the conventional departmental applications with professional look in web interface. The mobile version, on the other hand, is really cool and fun. The chapter devoted to this platform shows how to create the same desktop application for mobile devices. To save development efforts and time, you'll be guided to use existing tested application pages from the desktop version for the mobile platform. This work is produced with the intention to help those who are willing to learn how desktop and mobile web applications are developed, in minimal time frame. It is assumed that the users of this book have basic knowledge of SQL, PL/SQL, and have exposure to Oracle database objects. From APEX introduction to application development, and from dual version development to its deployment, this book is the ultimate practical guide for you to enhance your skills in an area which is the need of the hour.