OpenTripPlanner (OTP) is a family of open source software projects that provide passenger information and transportation network analysis services. The core server-side Java component finds itineraries combining transit, pedestrian, bicycle, and car segments through networks built from widely available, open standard OpenStreetMap and GTFS data. This service can be accessed directly via its web API or using a range of Javascript client libraries, including modern reactive modular components targeting mobile platforms (source: OpenTripPlanner Project).
OpenTripPlanner

OpenTripPlanner
Last checked for availability: Friday, November 15, 2019
Specifications
Description Webpage: http://www.opentripplanner.org/
Source code (download): https://github.com/opentripplanner/OpenTripPlanner
License type: Open source
Price scheme: N/A
Usage restrictions: N/A
Software platform: N/A
Code language: Java
API type: REST
API response type: JSON, XML
SDK: N/A