Transportr - The public transport companion that respects your privacy and your freedom.
Citymapper - The ultimate transport app - iPhone / Android / Web.
Google Maps - Find local businesses, view maps and get driving directions in Google Maps.
IDOS - Trains + Buses + All Public transport - Search for connection
Moovit - For people that use public trasnportation a lot, or who rarely use it but need to on occasion, it can be difficult at times to figure out where you need to be to get where you need to go. Read more about Moovit.
OsmAnd - Global mobile map viewing and navigation for online and offline OSM maps