Kevin Kimani's tutorial explores the integration of user authentication in React Native applications using Descope, a platform that simplifies the implementation of authentication methods such as passkeys and multi-factor authentication (MFA). Traditional authentication methods, like passwords, pose complexities related to security and development time, often requiring in-depth cryptography knowledge and leading to potential vulnerabilities. Descope offers a streamlined approach to managing these challenges by allowing developers to customize authentication flows and implement role-based access control (RBAC) without extensive coding. The guide walks through setting up a Descope project, modifying authentication flows, and integrating Descope with a React Native app, using a demo blogging platform as an example. This approach helps developers focus on core application features rather than on intricate security measures, offering a more efficient and secure solution for user authentication in mobile applications.