In transportation planning, the activity-based model system is considered as the next-generation demand foresting model and requires the input of trip modes and purposes of individuals. GPSbased travel surveys can avoid many problems in traditional paper and phone surveys and are becoming increasingly popular in major cities worldwide. In the past few years, Dr. Gong has developed a computing system consisting of a smartphone app that transmits GPS data to an Amazon cloud server where GIS algorithms detect travel modes and trip purposes of individuals. Because of the urban canyon effects and mixed land use typical in high-density cities such as New York, speculating trip purposes has proved to be very challenging without qualitative information from survey participants.