This disclosure generally relates to devices, systems, and computer-implemented methods for providing a graphical model editor that automatically arranges model entities and their relationships in a graphical manner. Specifically, methods are described herein for a graphical open data protocol model editor that automatically models entity relationships for a customized design of software applications. The methods comprise the operations of placing entities on a grid; drawing a horizontal pathway below the placed entities; dynamically adjusting the height of the rows; and drawing the associations of the entities placed on the grid, wherein spatial cross-over between the drawn associations may be reduced.