Harp has two key pieces of software that can deliver a standalone or integrated timetable system. The first is the image player software which runs a loop of images for each display head. This free runs on the central server. The images can be bmp, jpg, mpeg, flash or any other image format.

The second is an image renderer which takes raw text based timetable information and from it generate screen images. These screen images can be either destination screens or stand screens. Custom screens can also be configured.

Many different screen renders can run simultaneously creating image screens from various sources be they bus, flight, train or port. ATCO CIF and TransXchange formats are already available.