We present results from the design-based research and development process of a digital didactical tool connecting secondary and tertiary mathematics education among others by historical aspects and elements from Mathematics, Didactics, History, Literature and Technology especially for prospective mathematics teachers: Digital Interactive Mathematical Maps (DIMM), developed at the University of Passau, Germany. The DIMM for Geometry was integrated into a second semester course on Euclidean and non-Euclidean geometry in mathematics education at Karlstad University, Sweden, designed collaboratively by university mathematics lecturers and researchers in mathematics education from the cooperating universities. While, according to the results of evaluation, the (perceived) usefulness of individual functionalities of the digital tool was confirmed, the use of the DIMM in the courses seems to promote favorable beliefs about mathematics, too.