The speaker discussed how they use public transport data in their app, Caddy itinerary, which is a transport assistance app that allows users to import all kinds of travel-related information into a timeline. They explained the challenges of working with different ticket barcode standards and operator-specific extensions, and their reliance on donations of sample tickets to help decipher the proprietary codes. The speaker also talked about their use of real-time public transport information to notify users of delays, disruptions, and offer alternative journeys. They outlined the different sources they query for transport data and the abstraction layer they use to build on top of these sources. Additionally, they discussed the integration of rental vehicles, real-time status of elevators and escalators, and train coach layouts in their app. The talk highlighted the importance of open standards and data sharing to improve transport assistance services.