Types of Coverage
The Public Transit API offers three different levels of coverage: real-time, timetable and estimated.
Real-time information enables the consideration of current vehicle locations or sudden service disruptions to provide most-up to date expected arrival time of the Transit services at a particular station. In the context of routing, real-time information is considered within the route and journey calculation process. Current vehicle location messages alone cannot provide enough information to the user, this information needs to be matched with relevant journey information to be useful.
Public Transit sources detailed transit schedules from transit agencies; these may come in the form of actual times (for example, the train leaves the station at 09:18) or scheduled frequencies (for example, the bus runs every 20 minutes between the hours of 08:00 and 10:40 AM). In addition, timetable transit coverage areas are a more complete representation of the public transit networks available in a given city or metropolitan area.
With this level of support, the Public Transit API provides our best forecast of travel time based on the transit network configuration, stop density, vehicle type, and hours of operation of a given transit system when actual, granular transit timing information is not available. It should also be noted that there are cases where these coverage areas are only partially complete and may not include all of the public transit options that serve the city. This may include cases where the Public Transit API supports one or more but not all bus routes, for example.
* Limited geographic coverage
You can tailor transit route calculation for different use-cases by
- defining routes based on arrival time vs departure time
- selecting different forms of transit, such as rail, metro, bus, ferry
- planning routes hours or days in advance
- setting how far you are willing to walk to the nearest transit stop/station or the speed you normally walk
- defining how many changes or transfers you're willing to take on your journey