There are multiple location-based services (LBSs) and mobile GIS available for a wide range of applications. Usually such applications are developed to solve a restricted task within a restricted environment. The focus on a particular task is strong, and therefore, such applications can usually not be used in multiple environments. To overcome this issue, this paper presents a concept of a generic professional mobile GIS with a focus on interoperability. Firstly, common issues of mobile applications are presented, and their impact on the development of mobile GIS is analyzed. Subsequently, a new approach for a generic mobile GIS for professional users is presented. Based on multiple OGC standards, the approach leads to a system that can be used in various applications where the quality of surveyed data and analysis capabilities are improved. To prove the strength of the approach with GeoTechMobile, a prototype is presented and evaluated in a case study.