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 GTFS schedule is available for Porto, PT city buses here: https://opendata.porto.digital/dataset/horarios-paragens-e-rotas-em-formato-gtfs-stcp/resource/89a6854f-2ea3-4ba0-8d2f-6558a9df2a98

Can't find real-time, though I know it exists because there are apps that use it.