Full Stack Mobile Developer

**About the Role**   I am supporting a US healthcare client in hiring a **Full\-Stack Mobile Developer** to take end\-to\-end ownership of their flagship mobile application. In this role, you will serve as the **sole mobile developer** , responsible for evolving an app that pairs with a Bluetooth\-enabled pulse oximeter ring to capture overnight sleep data and securely upload it to the cloud. You won’t be working in isolation—while you’ll lead all mobile\-focused design and development, you’ll collaborate closely with a team of experienced C\#/.NET backend engineers. You’ll also contribute to backend features related to sleep\-study processing and data workflows, helping shape the overall product experience from device integration through clinical\-grade data analysis. This is an opportunity to own a critical mobile product in a modern health\-tech environment, working with senior engineers to deliver technology that directly impacts patient outcomes. The ideal candidate will have expertise in both mobile development (Flutter/Dart) and backend technologies (C\#/.NET), and be capable of ensuring seamless device integration, reliable overnight data collection, and robust backend connectivity with Azure services.    **Key Responsibilities**   * Lead the development and maintenance of cross\-platform mobile applications using Flutter/Dart for iOS and Android. * Implement and optimize Bluetooth connectivity with the ring pulse oximeter device. * Address Android battery optimization challenges to guarantee reliable overnight data collection. * Manage the release process for both the Apple App Store and Google Play Store. * Collaborate with backend developers on Azure\-hosted .NET services, contributing to backend development when required. * Ensure compliance with health data security and privacy standards. * Work independently while providing technical leadership within the team. **Requirements**   * Professional level English comprehension (spoken, reading/writing) * 7\+ years of professional software development experience, with strong expertise in mobile development. * Proven experience with  **Flutter/Dart**  for cross\-platform mobile applications. * Working knowledge of  **C\# and .NET** , with the ability to contribute to backend services. * Deep understanding of  **Bluetooth Low Energy (BLE)**  implementation. * Experience with  **Android battery optimization techniques**  for background processes. * Successful track record of publishing and maintaining apps in the App Store and Google Play. * Experience integrating with  **Microsoft Azure services** . * Familiarity with  **Firebase**  (Authentication, Crashlytics, Analytics),  **Sentry** , and  **PostHog** . * Advanced English communication skills ( **C1 level** ), both written and spoken. * Strong problem\-solving abilities and attention to detail. * Prior experience in health or medical app development is a plus.   **Technical Skills**   * **Primary:**  Flutter/Dart, Bluetooth LE, iOS, Android * **Secondary:**  C\#, .NET, Azure, Firebase * **Tools:**  GitHub, Sentry, PostHog, App Store Connect, Google Play Console **What We Offer**   * The opportunity to develop innovative health technology with real impact. * Competitive salary based on experience. * Professional growth and development opportunities. * A collaborative team culture that values independence and initiative.