Visual as-the-crow-flies (ATCF) navigation methods are an increasingly popular alternative to existing turn-by-turn (TBT) navigation for cyclists. To better understand how people use them in everyday navigation and how they cope with the novel navigation method in challenging situations, we studied two main issues posed by ATCF navigation: knowing whether one is on the right route to their destination and knowing whether a turn leads into a dead end or detour. To investigate these two problems, we compared visual ATCF navigation against (1) TBT navigation and (2) an improved ATCF+ navigation system in two successive studies. We found that users encountered problems riding in the opposite direction to the destination and were often turning around as a result using the ATCF method. Using colour cues in the ATCF user interface we were able to reinforce correct route choices. Additionally, we found that unsuccessful route progression negatively correlates with user confidence. CCS CONCEPTS • Human-centered computing → Human computer interaction (HCI); User studies; Field studies; Empirical studies in ubiquitous and mobile computing.

This paper presents Tiltification, a multi modal spirit level application for smartphones. The non-profit app was produced by students in the master project “Sonification Apps” in winter term 2020/21 at the University of Bremen to learn how to conceptualize, implement, market and test smartphone apps. In the app, psychoacoustic sonification is used to give feedback on the device’s rotation angles in two plane dimensions, allowing users to level furniture or take perfectly horizontal photos. Tiltification supplements the market of spirit level apps with detailed auditory information presentation. This provides for additional benefit in comparison to a physical spirit level and for more accessibility for visually and cognitively impaired people. We argue that the distribution of sonification apps through mainstream channels is a contribution to establish sonification in the market and make it better known to users outside the scientific domain.