I need a straightforward mobile application that runs natively on both iOS and Android. The first milestone is focused on a rock-solid user-authentication flow: email or username sign-up, secure password storage, session handling, and a clean, minimal interface that guides the user from onboarding to a basic home screen once they are signed in. Please build the project with an eye toward easy future expansion—while in-app payments and push notifications are not part of this phase, the architecture should leave room for those features when we’re ready. Feel free to suggest the tech stack you’re most productive with (Swift/Kotlin, React Native, Flutter, or similar) as long as the final deliverables meet these criteria: • Release-ready builds for both iOS and Android • Full, well-commented source code in a Git repository • A concise read-me explaining local setup, build steps, and any third-party services used (e.g., Firebase Auth, AWS Cognito) Clean code, clear commit history, and timely communication will be my benchmarks for success.