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GTFS at Trafiklab

At Trafiklab, we offer three GTFS feeds.

GTFS Sverige 2 which includes information for entire Sweden

GTFS Regional which consists of multiple GTFS feeds, each of which covers an operator in Sweden

GTFS Sweden 3 which is an aggregated dataset of all the different datasets in GTFS Regional. It gives a single GTFS feed for static data while the realtime feeds are, for performance reasons, split up by specific regions or operators

What is the difference?

It can be hard to understand the differences between all GTFS feeds but here is a short description. GTFS Sverige 2 is the only feed with complete coverage of operators in Sweden and only contains static data. GTFS Regional is per region/operator and perfect if you are interested in for example only SL or only Skånetrafiken. GTFS Regional also contains more details like for example shapes or stop points (instead of only stop areas) which is missing in GTFS Sverige. GTFS Sweden 3 is an aggregated dataset of all GTFS Regional so the level of detail is the same. The goal is to replace GTFS Sverige with this dataset but that requires a 100% coverage of operators which is not the case at the moment

You can see the general difference between GTFS Sverige 2 and GTFS Regional data below.

GTFS Sverige 2GTFS Regional/ GTFS Sweden 3
Coverage100%92%
Data qualityAverage qualityHigh quality, based on higher level of details
Real-time dataOnly static dataStatic + Real-time + GPS positions
Historical data (static)Since 2012Partly available in Koda

You can find the complete GTFS reference at https://developers.google.com/transit/gtfs/reference/.

You can find the complete GTFS-RT reference at https://developers.google.com/transit/gtfs-realtime/reference

If you want to learn about what GTFS is and how it works, read further down on this page.

Static GTFS files

What does each GTFS file contain

The content below is based on the official GTFS Specification, developed by the GTFS community and published at https://developers.google.com/transit/gtfs/reference/.

We modified the version below to describe the feeds published by Trafiklab. Fields and files that are not included in any Trafiklab feed are not described below. For the latest version or in case of conflict, refer to the official documentation.

  • In the tables below, the column ‘available in dataset’ will be bold if the field is always present and not bold if it is not always present.

agency.txt

Field NameTypeAvailable in datasetDescription
agency_idIDAllUniquely identifies a transit agency. Note that in some cases, such as when a single agency operates multiple separate services, agencies and brands are distinct. This document uses the term “agency” in place of “brand”. A dataset may contain data from multiple agencies.
agency_nameTextAllFull name of the transit agency.
agency_urlURLAllURL of the transit agency.
agency_timezoneTimezoneAllTimezone where the transit agency is located. If multiple agencies are specified in the dataset, each has the same agency_timezone.
agency_langLanguage codeAllPrimary language used by this transit agency
agency_fare_urlURLGTFS RegionalURL of a web page that allows a rider to purchase tickets or other fare instruments for that agency online

The following excerpt gives some example values for the different fields.

1agency_id,agency_name,agency_url,agency_timezone,agency_lang
2141010000000001418,Västtrafik,https://www.resrobot.se/,Europe/Stockholm,sv
3141010000000001001,Västtrafik Göteborgsområdet AB Lokaltrafik AB,https://www.resrobot.se/,Europe/Stockholm,sv
4141010000651668112,MTR Express (Sweden) AB,https://www.resrobot.se/,Europe/Stockholm,sv
5141010000452254130,Öresundståg,https://www.resrobot.se/,Europe/Stockholm,sv

routes.txt

Field NameTypeAvailable in datasetDescription
route_idIDAllIdentifies a route.
agency_idID referencing agency.agency_idAllAgency for the specified route. This field is required when the dataset provides data for routes from more than one agency in agency.txt, otherwise it is optional.
route_short_nameTextAllShort name of a route. This will often be a short, abstract identifier like “32”, “100X”, or “Green” that riders use to identify a route, but which doesn’t give any indication of what places the route serves. Either route_short_name or route_long_name must be specified, or potentially both if appropriate.
route_long_nameTextAllFull name of a route. This name is generally more descriptive than the route_short_name and often includes the route’s destination or stop. Either route_short_name or route_long_name must be specified, or potentially both if appropriate.
route_typeEnumAllIndicates the type of transportation used on a route.
route_urlURLNoneURL of a web page about the particular route. Should be different from the agency.agency_url value. Not used.
route_descTextGTFS RegionalDescription of a route that provides useful, quality information. Should not be a duplicate of route_short_name or route_long_name.

The GTFS standard defines 9 route_types, but all Trafiklab feeds make use of extended route types. Check the feed-specific documentation for examples.

The following excerpt shows some example values.

1route_id,agency_id,route_short_name,route_long_name,route_type
29011014280200000,141010000000001418,302,,717
39011014374100000,141010000000001418,420,,717
49011014471100000,141010000000001418,711,,700
59011014630400000,141010000000001418,304,,700

trips.txt

Field NameTypeAvailable in datasetDescription
route_idID referencing routes.route_idAllIdentifies a route.
service_idID referencing calendar.service_id or calendar_dates.service_idAllIdentifies a set of dates when service is available for one or more routes.
trip_idIDAllIdentifies a trip.
trip_headsignTextGTFS Sverige 2Text that appears on signage identifying the trip’s destination to riders. Use this field to distinguish between different patterns of service on the same route. If the headsign changes during a trip, trip_headsign can be overridden by specifying values for the stop_times.stop_headsign.
trip_short_nameTextGTFS Sverige 2Public facing text used to identify the trip to riders, for instance, to identify train numbers for commuter rail trips. If riders do not commonly rely on trip names, leave this field empty. A trip_short_name value, if provided, should uniquely identify a trip within a service day; it should not be used for destination names or limited/express designations.
direction_idEnumGTFS RegionalIndicates the direction of travel for a trip. This field is not used in routing; it provides a way to separate trips by direction when publishing time tables. Valid options are: 0 - Travel in one direction (e.g. outbound travel). 1 - Travel in the opposite direction (e.g. inbound travel).
shape_idID referencing shapes.shape_idGTFS RegionalIdentifies a geospatial shape describing the vehicle travel path for a trip.

The following excerpt shows what a trips.txt file can look like:

1route_id,service_id,trip_id,trip_headsign,direction_id,shape_id
29011014255000000,1,141010000961947846,,0,1
39011014255000000,1,141010000961947902,,0,1
49011014255000000,1,141010000961947958,,0,1
59011014255000000,1,141010000961948014,,0,1
This example doesn’t include a headsign, which means descriptions must be obtained from a higher lever (route) or lower level (stop time).

stop_times.txt

A stop time is a certain trip picking up or dropping of passengers at a certain stop, at a certain time.

Field NameTypeAvailable in datasetDescription
trip_idID referencing trips.trip_idAllIdentifies a trip.
arrival_timeTimeAllArrival time at a specific stop for a specific trip on a route. If there are not separate times for arrival and departure at a stop, enter the same value for arrival_time and departure_time. For times occurring after midnight on the service day, enter the time as a value greater than 24:00:00 in HH:MM:SS local time for the day on which the trip schedule begins.

Scheduled stops where the vehicle strictly adheres to the specified arrival and departure times are timepoints. If this stop is not a timepoint, it is recommended to provide an estimated or interpolated time. If this is not available, arrival_time can be left empty. Further, indicate that interpolated times are provided with timepoint=0. If interpolated times are indicated with timepoint=0, then time points must be indicated with timepoint=1. Provide arrival times for all stops that are time points. An arrival time must be specified for the first and the last stop in a trip.
departure_timeTimeAllDeparture time from a specific stop for a specific trip on a route. For times occurring after midnight on the service day, enter the time as a value greater than 24:00:00 in HH:MM:SS local time for the day on which the trip schedule begins. If there are not separate times for arrival and departure at a stop, enter the same value for arrival_time and departure_time. See the arrival_time description for more details about using timepoints correctly.

The departure_time field should specify time values whenever possible, including non-binding estimated or interpolated times between timepoints.
stop_idID referencing stops.stop_idAllIdentifies the serviced stop. All stops serviced during a trip must have a record in stop_times.txt. Referenced locations must be stops, not stations or station entrances. A stop may be serviced multiple times in the same trip, and multiple trips and routes may service the same stop.
stop_sequenceNon-negative integerAllOrder of stops for a particular trip. The values must increase along the trip but do not need to be consecutive.

Example: The first location on the trip could have a stop_sequence=1, the second location on the trip could have a stop_sequence=23, the third location could have a stop_sequence=40, and so on.
stop_headsignTextGTFS RegionalText that appears on signage identifying the trip's destination to riders. This field overrides the default trips.trip_headsign when the headsign changes between stops. If the headsign is displayed for an entire trip, use trips.trip_headsign instead.

A stop_headsign value specified for one stop_time does not apply to subsequent stop_times in the same trip.
ℹGTFS Regional specifies the stop_headsign for each stop
pickup_typeEnumAllIndicates pickup method. Valid options are:

0 or empty - Regularly scheduled pickup.
1 - No pickup available.
2 - Must phone agency to arrange pickup.
3 - Must coordinate with driver to arrange pickup.
drop_off_typeEnumAllIndicates drop off method. Valid options are:

0 or empty - Regularly scheduled drop off.
1 - No drop off available.
2 - Must phone agency to arrange drop off.
3 - Must coordinate with driver to arrange drop off.
shape_dist_traveledNon-negative floatGTFS RegionalActual distance travelled along the associated shape, from the first stop to the stop specified in this record. This field specifies how much of the shape to draw between any two stops during a trip. Must be in the same units used in shapes.txt. Values used for shape_dist_traveled must increase along with stop_sequence; they cannot be used to show reverse travel along a route.

Example: If a bus travels a distance of 5.25 kilometers from the start of the shape to the stop,shape_dist_traveled=5.25.
timepointEnumGTFS RegionalIndicates if arrival and departure times for a stop are strictly adhered to by the vehicle or if they are instead approximate and/or interpolated times. This field allows a GTFS producer to provide interpolated stop-times, while indicating that the times are approximate. Valid options are:

0 - Times are considered approximate.
1 or empty - Times are considered exact.
Stop_times.txt is usually the largest file in a GTFS feed. Depending on the hardware and programming language, it can be computationally intensive to read all the data. Make sure you read this file in an efficient way (for example by caching data, not reading the entire file into memory, …).

The following excerpt shows some stop_times from a GTFS Regional feed.

1trip_id,arrival_time,departure_time,stop_id,stop_sequence,stop_headsign,pickup_type,drop_off_type,shape_dist_traveled,timepoint
2        141010000961947846,08:30:00,08:30:00,9022014017767002,1,Borås,3,1,0,1
3        141010000961947846,08:32:00,08:32:00,9022014017513002,2,Borås,3,3,794,1
4        141010000961947846,08:32:51,08:32:51,9022014017516002,3,Borås,3,3,1071,0
5        141010000961947846,08:34:27,08:34:27,9022014017568002,4,Borås,3,3,1620.12,0

stops.txt

Field NameTypePresentDescription
stop_idIDAllIdentifies a stop, station, or station entrance. The term “station entrance” refers to both station entrances and station exits. Stops, stations or station entrances are collectively referred to as locations. Multiple routes may use the same stop.
stop_nameTextAllName of the location. Use a name that people will understand in the local and tourist vernacular. When the location is a boarding area (location_type=4), the stop_name should contains the name of the boarding area as displayed by the agency. It could be just one letter (like on some European intercity railway stations), or text like “Wheelchair boarding area” (NYC’s Subway) or “Head of short trains” (Paris’ RER).
stop_latLatitudeAllLatitude of the location. Conditionally Required:
Required for locations which are stops (location_type=0), stations (location_type=1) or entrances/exits (location_type=2).
• Optional for locations which are generic nodes (location_type=3) or boarding areas (location_type=4).
stop_lonLongitudeAllLongitude of the location. Conditionally Required:
Required for locations which are stops (location_type=0), stations (location_type=1) or entrances/exits (location_type=2).
• Optional for locations which are generic nodes (location_type=3) or boarding areas (location_type=4).
location_typeEnumAllType of the location:
0 (or blank): Stop (or Platform). A location where passengers board or disembark from a transit vehicle. Is called a platform when defined within a parent_station.
1: Station. A physical structure or area that contains one or more platform.
2: Entrance/Exit. A location where passengers can enter or exit a station from the street. If an entrance/exit belongs to multiple stations, it can be linked by pathways to both, but the data provider must pick one of them as parent.
parent_stationID referencing stops.stop_idGTFS Regional onlyDefines hierarchy between the differentlocations defined in stops.txt. It contains the ID of the parent location, as followed:
Stop/platform (location_type=0): the parent_station field contains the ID of a station.
Station (location_type=1): this field must be empty.
Entrance/exit (location_type=2) or generic node (location_type=3): the parent_station field contains the ID of a station (location_type=1)
platform_codeTextGTFS Regional onlyPlatform identifier for a platform stop (a stop belonging to a station).
1stop_id,stop_name,stop_lat,stop_lon,location_type,parent_station,platform_code
29021014016110000,Bruksvägen,57.828220,12.014754,1,,
39021014016113000,Idrottsvägen,57.837484,12.014661,1,,
49021014016118000,Surte kyrka,57.831229,12.013882,1,,
59021014016212000,Skolvägen,57.848549,12.014318,1,,

calendar.txt

Field NameTypePresentDescription
service_idIDAllUniquely identifies a set of dates when service is available for one or more routes. Each service_id value can appear at most once in a calendar.txt file.
mondayEnumAllIndicates whether the service operates on all Mondays in the date range specified by the start_date and end_date fields. Note that exceptions for particular dates may be listed in calendar_dates.txt. Valid options are: 1 - Service is available for all Mondays in the date range. 0 - Service is not available for Mondays in the date range.
tuesdayEnumAllFunctions in the same way as monday except applies to Tuesdays
wednesdayEnumAllFunctions in the same way as monday except applies to Wednesdays
thursdayEnumAllFunctions in the same way as monday except applies to Thursdays
fridayEnumAllFunctions in the same way as monday except applies to Fridays
saturdayEnumAllFunctions in the same way as monday except applies to Saturdays.
sundayEnumAllFunctions in the same way as monday except applies to Sundays.
start_dateDateAllStart service day for the service interval.
end_dateDateAllEnd service day for the service interval. This service day is included in the interval.
Trafiklab feeds use the calendar.txt file to define the periods during which lines are operated/valid. The actual operating days are defined in calendar_dates.txt.
1service_id,monday,tuesday,wednesday,thursday,friday,saturday,sunday,start_date,end_date
21,0,0,0,0,0,0,0,20200221,20200612
32,0,0,0,0,0,0,0,20200222,20200613
43,0,0,0,0,0,0,0,20200223,20200614
54,0,0,0,0,0,0,0,20200615,20201211

calendar_dates.txt

Field NameTypePresentDescription
service_idID referencing calendar.service_id and trips.service_idAllIdentifies a set of dates when a service exception occurs for one or more routes. Each (service_id, date) pair can only appear once in calendar_dates.txt if using calendar.txt and calendar_dates.txt in conjunction. The information in calendar_dates.txt modifies the service information specified in calendar.txt
dateEnumAllDate when service exception occurs.
exception_typeEnumAllIndicates whether service is available on the date specified in the date field. Valid options are:

1 - Service has been added for the specified date.
2 - Service has been removed for the specified date.

Example: Suppose a route has one set of trips available on holidays and another set of trips available on all other days. One service_id could correspond to the regular service schedule and another service_id could correspond to the holiday schedule. For a particular holiday, the calendar_dates.txt file could be used to add the holiday to the holiday service_id and to remove the holiday from the regular service_id schedule.
1service_id,date,exception_type
21,20200221,1
31,20200224,1
41,20200225,1
51,20200226,1

shapes.txt

Field NameTypePresentDescription
shape_idIDGTFS RegionalIdentifies a shape.
shape_pt_latLatitudeGTFS RegionalLatitude of a shape point. Each record in shapes.txt represent a shape point used to define the shape.
shape_pt_lonLongitudeGTFS RegionalLongitude of a shape point.
shape_pt_sequenceNon-negative integerGTFS RegionalSequence in which the shape points connect to form the shape. Values must increase along the trip but do not need to be consecutive.
shape_dist_traveledNon-negative floatGTFS RegionalActual distance traveled along the shape from the first shape point to the point specified in this record. Used by trip planners to show the correct portion of the shape on a map. Values must increase along with shape_pt_sequence; they cannot be used to show reverse travel along a route. Distance in kilometres.
1shape_id,shape_pt_lat,shape_pt_lon,shape_pt_sequence,shape_dist_traveled
21,57.927181,12.529311,1,0
31,57.927172,12.529295,2,0
41,57.927397,12.529314,3,24.31
51,57.927398,12.529364,4,27.89

transfers.txt

Field NameTypePresentDescription
from_stop_idID referencing stops.stop_idAllIdentifies a stop or station where a connection between routes begins. If this field refers to a station, the transfer rule applies to all its child stops.
to_stop_idID referencing stops.stop_idAllIdentifies a stop or station where a connection between routes ends. If this field refers to a station, the transfer rule applies to all child stops.
transfer_typeEnumAllIndicates the type of connection for the specified (from_stop_id, to_stop_id) pair. Valid options are:

0 or empty - Recommended transfer point between routes.
1 - Timed transfer point between two routes. The departing vehicle is expected to wait for the arriving one and leave sufficient time for a rider to transfer between routes.
2 - Transfer requires a minimum amount of time between arrival and departure to ensure a connection. The time required to transfer is specified by min_transfer_time.
3 - Transfers are not possible between routes at the location.
min_transfer_timeNon-negative integerAllAmount of time, in seconds, that must be available to permit a transfer between routes at the specified stops. The min_transfer_time should be sufficient to permit a typical rider to move between the two stops, including buffer time to allow for schedule variance on each route.
from_trip_idID referencing trips.trip_idAllIdentifies a trip where a connection between trips starts. If empty, this rule applies for all trips.
to_trip_idID referencing trips.trip_idAllIdentifies a trip where a connection between trips ends. If empty, this rule applies for all trips.
1from_stop_id,to_stop_id,transfer_type,min_transfer_time,from_trip_id,to_trip_id
29022014061616002,9022014061616002,1,,141010000981658971,141010000967489295
39022014080420002,9022014080420002,1,,141010000981659030,141010000981658971
49022014080437002,9022014080437002,1,,141010000981659030,141010000981664702
59022014080437002,9022014080437002,1,,141010000981659030,141010000981664817

GTFS Extensions

Both GTFS Sverige 2 and GTFS Regional uses some of the GTFS Extensions. These extensions are not part of the specification, but are additions to offer additional details.

Extended Route Types

Extended route types allow for more specific transport modes to be used. GTFS Sverige and GTFS Regional does not use the standard one digit GTFS route types, but only uses extended route types.

The following list shows the most used transport modes for GTFS Sverige and GTFS Regional. This is a non-extensive list, only meant to give an idea of the types you should support. You should still be able to handle the other types in a graceful way, as new traffic may make use of them without prior warning.

CodeNameExample
100Railway Service
101High Speed Rail ServiceX2000
102Long Distance Rail ServiceMälartåg
105Sleeper Rail ServiceNight train (Nattåg)
106Regional Rail ServiceCommuter trains (Pendeltåg)
401Metro ServiceTunnelbanan Stockholm
700Bus Service
702Express Bus Service
717Share Taxi ServiceAdvance order traffic (Förbeställningstrafik)
900Tram ServiceTrams in Göteborg
1000Water Transport ServiceSL Pendelbåt, Stockholm-Helsinki
1501Communal Taxi ServiceBuses with advance order conditions (Förbeställningstrafik)

A complete list of all route types can be found at https://developers.google.com/transit/gtfs/reference/extended-route-types .

Trip-to-trip transfers

GTFS Sverige 2 and GTFS Regional includes trip-to-trip transfers, which are detailed transfer rules that provide additional details on which transfers are possible, and how long they take.

Trip-to-trip transfers used to be an extension to the GTFS standard, but this extension has been formally adopted into the GTFS standard in October 2021.

Trip to trip transfers make use of the from_trip_id and to_trip_id columns in the transfers.txt file.

From Googles documentation: The from_trip_id and to_trip_id fields can contain a trip_id, as specified by trips.txt. If from_trip_id is specified, the transfer will only apply to the arriving trip with the given trip id, at the given from_stop_id. If to_trip_id is specified, the transfer will only apply to the departing trip with the given trip id, at the given to_stop_id.

Realtime GTFS files

Realtime data refers to elements defined in the static data. You therefore need to download both the static dataset and the realtime files if you want to make use of Realtime GTFS.

We will only discuss the general working and contents of GTFS Realtime feeds. You can find the complete technical specification at https://developers.google.com/transit/gtfs-realtime/.
GTFS Realtime communicates deviations from the data in the static GTFS file. You need both in order to create realtime timetables.

The GTFS Realtime standard uses the protobuf format to transfer compact messages which describe deviations between the real world and the schedules for a public transport network. There are 3 different feeds, each of which provides their own type of information.

ServiceAlerts

ServiceAlerts provide information about incidents, planned maintenance, … which affect more than one or a couple of trips. They can describe a closed station, incidents like electricity failures or defect trains, extra services for certain events, … . They typically contain similar information as the messages shown on digital signs in stations. Usually a header, description and link are provided, along with a cause and an effect (provided as an enum). Service alerts can be limited in time or to certain agencies, trips, stops, transport types, …

TripUpdates

TripUpdates provide information about deviations between the scheduled timetable of a trip and the real world. This can be a delay, a vehicle running early, a partial cancellation, a platform change, … . Each TripUpdates file contains multiple TripDescriptors, each of which describes deviations in a trip. If a scheduled trip isn’t present in a TripUpdates file, this can both mean that there are no delays, or that no information is available.

VehicleUpdates

VehicleUpdates contain realtime GPS positions of public transport vehicles. These allow you to see where a vehicle is located, along with its speed and bearing. These can be used to show vehicles on a map, to analyze traffic congestion, …

Continue reading


GTFS basics

What is GTFS?

The General Transit Feed Specification is a file format which originally was developed by Google in 2006. It combines all the data in one compact file. This means you can download a single file to get timetable information for the entirety of Sweden. The GTFS standard defines files which must be present in the dataset, and files which are optional. In this guide we will only discuss the files which are present in the Trafiklab datasets.

The GTFS Standard consists of 2 parts: static and real-time data. In the following sections, we will help you to get started with both.

How does GTFS Work?

A GTFS file is a zip archive that contains several *.txt files. You can compare this archive file with a database. The files inside the archive contain Comma Separated Values (CSV) data, meaning they are easy to read, both for computers and humans. Each file contains all the instances of a certain type, just like a database table. For example, one file contains all the routes, another file contains all the stops. The files are linked together through ids, similar to how foreign keys work in a database. The image below gives an idea of the structure.

GTFS Sverige 2 does not contain a shapes.txt file

The GTFS model, as used by Trafiklab. Fields which are always present are marked in bold.
The GTFS model contains multiple files, which can be required or optional. The fields in these files can be always present, present for certain feed (e.g. only in GTFS Regional) or optional. The diagram above shows which fields are used by Trafiklab. The fields which are always present in a file are marked in bold. The tables marked in green are required by the GTFS standard, the blue ones are optional files used in the Trafiklab data.

A GTFS archive forms a database-like structure with every file as one table, and you can import these CSV files directly into a new database to run queries on them. One example is the csv2db tool, but there are many other ways to achieve this.

How it is linked together

Before diving deeper into what each field means, it’s important to understand how transport data is described in the 7 required files.

A certain “path” on which public transport vehicles travel, is called a route and defined in routes.txt. A route is provided by a public transport agency (defined in agencies.txt), and can be serviced one or more times in a day. Every trip on a route is defined in the trips.txt file.

Example: Let’s say there is a route “Stockholm - Skövde - Göteborg”. There is a train leaving stockholm at 10:00, 12:00, and 16:00. In this case, we have one route with three trips on that route.

Different trips on the same route might make use of different stops.

The stops which are made during a trip are defined as stop times in stop_times.txt. A stop time does not contain information about the stop itself: it only links a trip to a stop, and includes some additional information such as the time of arrival and departure. Stops itself are defined in the stops.txt file, including information such as their name, location and entrances.

Example: Let’s say there is a trip on the route “Stockholm - Skövde - Göteborg” leaving at 10:00. The GTFS file would contain the trip, 3 stops, and 3 stop_times to link the stops to the trip.

When should I use GTFS?

A dataset like GTFS is the opposite of an API like ResRobot. Each has its own benefits and drawbacks. When you want to create a simple app, or let users search for the next departure from your website, an API is easier to use. However, when you want to analyze data, an API would need millions of requests compared to a single GTFS file that has all the data.

Well suited forNot so suited for
Analysing (real-time) transport dataQuickly getting the next departures from a stop
Building your own route-planner or APIQuickly calculating a route from A to B
Getting a list of all public transport stop-areas for an operator or a countryProjects where large files (>25MB) can’t be used
Getting the live position of all public transport vehicles
There are hundreds of libraries, examples and demos for GTFS. You can find some at https://github.com/andredarcie/awesome-gtfs and https://github.com/CUTR-at-USF/awesome-transit.