Explore a comprehensive conference talk on achieving sustainable growth in mobile app development, focusing on Busuu's strategies for user engagement from pre-installation to post-registration. Learn how to optimize onboarding, enhance first-time user experiences, and implement post-registration initiatives to maintain user commitment and long-term goal focus. Discover techniques for visualizing data, creating customer journey maps, and conducting rapid experiments to improve install conversion rates. Gain insights into developing effective study plans, behavioral models, and retention strategies. Understand the impact of language selection, notifications, and registration processes on user engagement. Examine how Busuu's cross-team collaboration drives holistic growth strategies for their 90 million users.