chapter 1 Building Your First App While Exploring the Interface
chapter 2 Programming and Design Fundamentals
In Part I, you stick your toe into the waters of App Inventor. Chapter 1 gets you started right away by walking you through the creation of a simple app as a way to get familiar with the App Inventor user interface. Chapter 2 is a primer on programming and design fundamentals. In that chapter, I cover how to refine design goals, work with primitives, and introduce you to must-know programming terminology.
If you are a more advanced App Inventor user, you may want to flip right to Part II to get started building some more challenging apps.