Mobile app security is crucial for every application, regardless of its scale, to protect user data, maintain trust, and ensure regulatory compliance. Founders should prioritize security from the outset, whether coding from scratch or using a no-code platform like Bubble, which offers tools to simplify this process. Key areas to focus on include data storage, communication security, authentication, and authorization, all of which help prevent unauthorized access and data breaches. Compliance with laws such as GDPR and CCPA is essential to avoid legal penalties and loss of user trust. Bubble enhances security by providing built-in encryption, user authentication, and access controls, along with automated security scanning through Flusk, which helps identify potential vulnerabilities. By implementing best practices like limiting access, using secure code, and regularly testing and monitoring security measures, developers can build robust mobile apps that protect both their business and user data effectively.