Three Challenges for Multi-Modal Trip Planning Apps

Trevor Gerhardt, a developer with Conveyal who works with OpenTripPlanner, shares some of the problems that arise for plotting multi-modal routes on mobile apps.

Gerhardt introduces the difficulties in multi-modal trip planning by explaining the process by which his team has refined the process for the Washington, D.C.-focused app CarFreeAtoZ: "In the backend of CarFreeAtoZ, we take our search a step further and use subjective values to rank each option based on more than just time. This allows us to tailor options to each commuter as well as the full community in aggregate, instead of just showing the fastest possible trip by default. It also creates a split where we determine which routes to prune by objective measures and which to score and re-rank with subjective ones."

Gerhardt goes on to explain that such a process creates several categories of challenges, including "bike-to-transit pushing out walk-to-transit," "longer transit wait times than ride times," and "when to hide drive-to-transit results." Gerhardt also explains the CarFreeAtoZ approach to each of these challenges and solicits feedback on the routes provided by that system.