At present, many smart cities are building a "geographic medium" mobile innovation network. As a new medium for urban public space, "interface" has become an important carrier for urban social governance, spatial production, and design behavior. The work aims to reveal the mechanism of "interface" in the smart city life system and innovation system, explore the ways to position and design the "interface" of smart cities in China in the new era, and provide relevant strategies. Starting from the field of media environment, this method focused on the context of interface related concepts such as "geomedia" and "Media City", and conducts theoretical tracing, case analysis, and practical speculation around the living facilities, governance tools, and communication environment of interface positioning. In conclusion, with the continuous development of artificial intelligence and the deep integration of new and old media, "interface" has become an important lever for innovation in smart cities. However, currently, due to the technical masking of the "communication perspective", it is mostly deconstructed as a decorative means of the city. The "interface" should become an important area of concern for explicit social governance, and design as a tangible practice of media can directly act on the "residents-interface-space" to form a fluid strategy. The construction of practical significance can be completed by linking "physical logic", "behavioral logic", and "aggregation logic" contained in interfaces. This has important application value for strengthening urban differentiation positioning, innovating in urban governance paths, and promoting the external dissemination of urban image.