A Global Mapper developer works on the Global Mapper software, a geographic information system (GIS) application, providing solutions for mapping and spatial data analysis. They are responsible for designing, coding, and modifying the software, aligning with user needs for data processing and visualization. They work on improving the software's functionality, incorporating geospatial data viewing, conversion, and editing features. They also troubleshoot issues, provide technical support, and develop new tools for better data management. They often work with various data formats and coordinate systems, ensuring seamless data integration and analysis.