Journal of Cognitive Human-Computer Interaction JCHCI 2771-1463 2771-1471 10.54216/JCHCI https://www.americaspg.com/journals/show/3993 2021 2021 HeartLink: IoT Smartwatch for Emergency Alerts Assistant Professor, Department. Of AI&DS, Panimalar Engineering College, India A. A. Students, Department. Of AI&DS, Panimalar Engineering College, India Cherlin Flory Thomas Students, Department. Of AI&DS, Panimalar Engineering College, India Anu Sushmitha. S. This paper introduces HeartLink, an IoT-based health monitoring system designed to provide real-time heart rate tracking and emergency alerts using the Huawei Band 9 smartwatch. The system integrates Huawei's Health Kit with a Flutter-based Android application, enabling seamless data collection and processing. The backend, built on Java Spring Boot or Node.js, utilizes a hybrid database architecture combining MongoDB and Firebase for efficient data storage and real-time synchronization. HeartLink features threshold- based alert mechanisms, where heart rate deviations trigger SMS notifications to pre-selected contacts via Twilio and emergency calls to ambulance services in critical scenarios. Firebase Cloud Messaging (FCM) ensures timely push notifications, while Firebase Authentication secures user access. The system's modular design allows for real-time heart rate analysis, dynamic threshold configuration, and automated emergency responses, making it a robust solution for individuals requiring continuous health monitoring. By leveraging advanced IoT and cloud technologies, HeartLink bridges the gap between wearable health devices and emergency response systems, offering a scalable, reliable, and user-friendly platform for real-time health tracking and life- saving interventions. 2025 2025 01 13 10.54216/JCHCI.100101 https://www.americaspg.com/articleinfo/25/show/3993