A jQuery developer designs, implements and manages web applications using the jQuery library. They create interactive elements to enhance user experience, troubleshoot and fix bugs, and optimize web pages for maximum speed and scalability. Furthermore, they ensure the compatibility of applications across different browsers and platforms. Their responsibilities also include collaborating with other team members and stakeholders, understanding client requirements, and converting them into technical specifications. They must also stay updated with the latest industry trends and advancements in jQuery and related technologies. Their ultimate goal is to create high-performance, user-friendly web applications that serve business needs.