This paper presents the design and development of a real-time chat application using the MERN stack (MongoDB, Express.js, React.js, Node.js) integrated with Socket.IO for real-time bidirectional communication. The system enables users to exchange messages instantly with features such as message delivery status, typing indicators, and online presence tracking.The application addresses key challenges in real-time systems including message synchronization during network interruptions, efficient event handling, and scalable architecture. A robust solution for lost message recovery was implemented using reconnection handling and API-based message fetching.The system was developed following Agile methodology and tested using structured test cases. Results demonstrate reliable performance with low latency communication and improved user experience.
Hemant Soni (Wed,) studied this question.