My agency is looking to develop an application that uses a list of one or more U.S. county names and a county designation for each one to compute a funding formula. We have ArcGIS Pro desktop and ArcGIS Online and a web map of the counties and their designations, and we'd like to use a map interface to populate the county designation string. Can ArcGIS Online be used to develop a web-based, map interface application where counties are selected on the screen and then input into a formula or would ArcGIS Enterprise be needed? Can the ArcGIS Online map rest endpoint be accessed by other applications? I'm not sure which develop environment or coding language would be used at this point.