Thank you very much for your interest in Android! Android is moving forward from year to year and 2019 Android Q continues this trend. Many programmers ignore new versions of Android until a specific problem disappoints them. We hope you're reading this ahead of time before Android Q ships to lots of devices, so you can avoid any problems before they turn into customer complaints. This book is intended for developers with over 1 year of experience in developing Android apps. If you're new to Android, consider reading "Elements of Android Jetpack," "Exploring Android" or both before continuing to read this book. Also note that examples of this book are written in Kotlin.