Discover tools and strategies to enhance user engagement and retention in this Google I/O '17 conference talk. Learn how to leverage Google Play, Firebase, and Google Identity to optimize key aspects of the user experience, including onboarding, personalization, and notifications. Explore topics such as defining engagement objectives, ensuring app stability, implementing Google Sign-in, and utilizing push notifications effectively. Gain insights from successful apps like Freeletics, OneFootball, and Citymapper. Understand the importance of relevance, actionable notifications, and rich content in keeping users engaged. Dive into the Awareness API and Firebase Notifications to create more personalized experiences. Conclude with an App Engagement Checklist to help you build a more successful app. Suitable for beginner to intermediate level developers and product managers looking to connect with over 1 billion users globally through Google Play.