Abstract: An ergonomic graphical user interface in a mobile device allows a user to use the mobile device effectively with one hand. The ergonomic user interface organizes icons representing related application programs into common arcs. Such arcs serve as a convenient gateway to apps of a specific context category and thus enhance the ability to comfortably use the mobile device using only one hand. The advantages are achieved by basing the interface design on ease of interaction with the touch screen using the natural range of motion of the human thumb. Related application programs may share data, information and resources. A sever may interact with the related applications to provide additional services and analytical information based on the shared data.