We're working on live public transport schedules as the first step to public transport routing. Here is the helper web app that shows currently supported GTFS feeds in different countries and cities and helps to match bus/tram/train stops from OpenStreetMap.org with stops from GTFS: https://gtfs-osm-matcher.organicmaps.app/
If you are interested in public transport schedules in your city, please let us know about feeds for your place/country, and help by adding/editing stops in OpenStreetMap.org

@organicmaps Here's the static GTFS for Vigo, Spain. The only problem is the transit information is loaded as calendar_dates items and only for a few days, meaning you have to either reimport it or manually modify it to make it "long-term" somehow. https://datos.vigo.org/data/transporte/gtfs_vigo.zip

There's also a feed for Xunta de Galicia (regional transit authority), but the data quality is not great. You need to sign up (for free) to the spanish NAP to download feeds
https://nap.transportes.gob.es/Files/Detail/1386