Build cross-platform apps with Flutter (Dart) for iOS, Android, and Web. Design, develop, and maintain scalable backend APIs (REST/GraphQL) and cloud services. Integrate Firebase (Auth, Firestore, Cloud Functions, FCM) and GCP (Cloud Run, Vertex AI). Connect third-party APIs, AI/ML services, and multimedia data flows. Optimize app performance for low-bandwidth users and ensure seamless UX. Implement Firebase Security Rules and manage real-time databases. Partner with designers to transform UX/UI mockups into functional experiences. Write clean, documented code following best practices; troubleshoot and debug issues. Lead deployments to App Store and Google Play.