A Java Wireless Toolkit developer primarily designs, implements, and maintains Java applications for wireless devices like mobile phones or tablets. They use Java Platform, Micro Edition (), and other wireless development tools to create software for small, resource-constrained devices. Their responsibilities include writing efficient, scalable code, debugging software, and integrating applications with back-end services. They also ensure the compatibility of their applications across multiple devices and versions. Additionally, they collaborate with cross-functional teams to define, design, and ship new features, and they continuously discover, evaluate, and implement new technologies to maximize development efficiency.