A comprehensive understanding of transport demand is required for the evidence-based design of a climate and environmentally friendly mobility systems. The data sources currently used are inadequate, particularly in rural areas with a less diverse range of mobility options and when it comes to the needs of vulnerable groups of people. As a result of advancing digitalisation, data sources other than traditional mobility data (such as big data from earth observation or social media platforms) are becoming available, providing the potential to make a significant contribution to a better understanding of transport demand.