This web app models the likelihood of transit use for various population groups and trip purposes. By automating complex spatial analyses, the tool enables Foursquare ITP planners to develop high quality transit service recommendations quickly. Numerous Census demographic and socioeconomic datasets are combined with jobs data to generate four indices of relative transit propensity for a given study area. Foursquare ITP planners use these results to understand the kinds of service each area needs, from high-frequency transit to lifeline connector services. The tool can also be customized to calculate bikeshare propensity indices and to incorporate zoning or other land use conditions. The web app automatically renders interactive maps of results and generates downloadable GIS outputs, allowing Foursquare ITP to conduct detailed analyses very efficiently.