Schedule management of construction work is critical to completing construction projects within a given period of time. Many efforts have been made and multiple tools have been developed to support the management of construction projects using smart devices such as smartphones and tablet PCs. This study proposed a method for managing construction schedules via a smart device using Flash. The interactive and graphic properties of Flash enable the development of an app that can allow a field manager to manage schedules easily and efficiently. A prototype was implemented using Adobe Flex Builder, and a sample network was applied in a smartphone. It is convenient for a construction manager to manage construction schedules using the tool because Flash controls graphic components easily. In further studies, network diagrams such as CPM (Critical Path Method) should be developed and applied to the app.