Senior Full stack mobile developer English B2+

WE ARE LOOKING FOR CANDIDATES FROM COLOMBIA, BRAZIL AND ARGENTINA 🌐 Full Stack Mobile Developer 📍 Location: Remote 🕒 Schedule: Monday to Friday, full\-time office hours 💼 Job Type: Full\-time 🌎 English Level: C1 (advanced proficiency required) 🚀 About the Role We are looking for a Full Stack Mobile Developer to take ownership of our health monitoring mobile application. This application integrates with a Bluetooth\-enabled ring pulse oximeter to collect health data throughout the night. You will be hands\-on across mobile (Flutter/Dart) and backend technologies (C\#/.NET \+ Azure), ensuring seamless device integration, reliable overnight data collection, and robust backend connectivity. Approximately 50–70% of the role will be focused on backend development using .NET and Azure, while the remaining time will be dedicated to mobile app development and integration. 🎯 Key Responsibilities * Lead the development and maintenance of cross\-platform mobile apps (Flutter/Dart for iOS \& Android). * Implement and optimize Bluetooth LE connectivity with the ring pulse oximeter. * Address Android battery optimization challenges for overnight data collection. * Manage App Store \& Google Play release processes. * Collaborate with backend developers on Azure\-hosted .NET services, contributing to backend code as needed. * Ensure compliance with health data security \& privacy standards. * Work independently while providing technical leadership to the team. ✅ Requirements * 7\+ years of professional software development experience, with strong expertise in mobile development. * Proven experience with Flutter/Dart for cross\-platform apps. * Working knowledge of C\# and .NET, with the ability to contribute to backend services. * Deep understanding of Bluetooth Low Energy (BLE). * Experience with Android background/battery optimization. * Successful track record of publishing apps in App Store \& Google Play. * Experience integrating with Microsoft Azure services. * Familiarity with Firebase (Auth, Crashlytics, Analytics), Sentry, and PostHog. * Advanced English (C1\), written and spoken. * Strong problem\-solving and attention to detail. * Prior health/medical app experience is a plus. 🛠️ Technical Stack Primary: Flutter/Dart, Bluetooth LE, iOS, Android Secondary: C\#, .NET, Azure, Firebase Tools: GitHub, Sentry, PostHog, App Store Connect, Google Play Console. Be sure to highlight your experience with backend development (.NET), Bluetooth implementations, and mobile app development.