It would be nice to have web apps that work offline and send push notifications. This is now possible with Service Workers, which can add native-like functionality to your web apps without requiring a download. This book will get your mobile and web apps functioning without Internet connectivity, improve performance and network interaction in order to increase the level of availability, and show you how to build performant applications that seamlessly integrate with third-party APIs. We’ll show you how to add Service Worker functionality to web apps and sites, access offline content through basic and advanced techniques, and build powerful interactive system notifications. We’ll also teach you about cache functionality and assets to provide immediate load even over narrow connections. We conclude by giving you various tips to improve app performance, including the background sync technique. By the end of this book, you’ll know build high performing and faster web and mobile applications with Service Workers.