Smart City has been envisioned as one vital solution for developing cities around the world to improve living quality of cities. In spite of different definitions of Smart City, one essential element in Smart City is smart transport or smart mobility. How to improve transport through future technologies is an important issue in developing smart cities. In this study, a smart city framework for Chiayi City (Taiwan) is proposed. The framework is described in eco transportation modes, including electric bicycle, electric moped, electric vehicle, and electric bus to provide different levels of mobility. Numerical analysis based on current transit demand data is conducted to examine possible alternatives. The concept of electric bus in conjunction with demand responsive transit service is examined numerically by solving number of dispatched vehicles, capacity, and drivers. However, due to available data, cost of diesel bus is used in financial analysis as an illustration for the Chiayi City.