OpenTripPlanner VS meetgowhere

For a full multimodal routing engine including realtime data for transit, you should have a look at OpenTripPlanner version 2 (if you haven't already): https://www.opentripplanner.org/

OTP (https://www.opentripplanner.org/) is an OpenSource Software written in Java, that is designed to use open data sources OpenStreetMap (OSM) and the GTFS data. It allows users to plan a trip that can combine multiple modes of transportation, such as bicycling or walking to reach public transportation. It can deal with Interlines (transfers) between different public transportation systems. Users can specify departure or arrival times for public transportation to build isochrones.

It's provided by OpenTripPlanner, the public transport data I managed to find around 2-3 years old, so I doubt it is very accurate. The usual google maps / citymapper and other routing services doesn't provide a way to generate the public transport isochrone or is too expensive/restricted

I've also used OpenTripPlanner for the same purpose in the past and it does generate higher-resolution isochrones but it's also more difficult to use and less flexible in its analysis options.

The source code is here, it might be a bit messy haha. There is no algorithm essentially, I used a bunch of open source software to do all the work. OpenTripPlanner for the public transport isochrones, MapBox Isochrone API for driving isochrone, and turf.js to calculate polygon intersections.