The project to develop and deliver the Southeast Map app for Network Rail used leading-edge mobile technologies to process and present large amounts of publicly available train running data seamlessly, enabling operational staff to make better informed decisions, enable faster recovery of rail network performance following incidents and provide better quality information to passengers. Its unique value is in the way live data is presented through a simple and recognisable map-based interface. Information that was previously delivered in a complex and inefficient way is now available at a glance to a wider customer base, reducing costs and improving insight, responsiveness and communication with passengers. From the initial customer requirement the project used agile delivery techniques to provide a proof of concept, engage the customer through collaboration, manage complex data and undertake testing to deliver a highly innovative product.