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.