The challenge of retaining users in mobile apps is significant, with 71% of all app users churning within 90 days. To address this issue, effective onboarding flows are crucial, as they can make or break the user experience. There are four key best practices for creating successful onboarding flows: highlighting emotional value, showcasing competitive features, delivering a first 'A-ha moment', and personalizing it for users. Additionally, considering factors such as progress status, opt-out options, check-out processes, and multi-session users can further enhance the overall user experience.