Explore a conference talk that delves into the vulnerabilities of Google Play Billing API and demonstrates how attackers can bypass payment processes in popular Android games. Learn about the billing workflow, known vulnerabilities, and real-world examples of compromised applications. Discover techniques used by developers to protect billing processes and how reverse engineering can still circumvent these measures. Gain insights into the number of vulnerable applications and compare Google's billing system with alternatives from Amazon and Samsung. Understand the implications for developers and users, and explore potential solutions to enhance security in mobile app transactions.