Grocery shopping is a regular necessity typically conducted in-store, with available alternatives such as online grocery shopping still not fully established yet. To address challenges experienced by shoppers in a store environment, two supporting modes were derived, implemented in a prototypical smartphone application using a minimal attention user interface and evaluated in an experimental field study. The two supporting modes consist of a novel map representation of shopping lists and a contextual proximity notification system. The evaluation results show an increase in efficiency in the process of grocery shopping, resulting in reduced shopping time, optimized shopping paths in the store, minimized dependency on external support and preservation of the shopper's cognitive effort. Acceptance of the introduced supporting modes was high which is a crucial indicator for future work.

Entering text is a fundamental part of how we interact with computing devices. The predominant form of text input on smartphones are virtual keyboards, which provide greater flexibility and customization options compared to hardware keyboards. Mobile text entry performance has been widely studied in HCI research, with most experiments being conducted in a controlled, artifical lab environment. To escape the boundaries of the lab and observe mobile text entry behaviour in a realistic and natural environment, we developed and publicly released the game Hyper Typer on Google Play Store. Hyper Typer is a serious research game for measuring mobile text entry performance and behaviour on a large scale in the real world. Publishing the game on Google Play Store resulted in a total of 2,359 valid transcribed phrases with 71,963 keystrokes. In this paper we discuss the game design of Hyper Typer, present the results collected over a time period of one year after the release of the game and reflect on the advantages, disadvantages and challenges of deploying a research game publicly.

While mobile gamified apps for language learning such as Duolingo are highly successful, knowledge about the use and suitability of such concepts for blended learning in schools is scarce. Pursuing a holistic approach, this work investigates the general requirements and acceptance of a modern gamified learning companion for traditional class-based teaching. We conducted several surveys with students, teachers and parents and studied the usage of a custom research prototype by 13/14-year-olds in three classes in English (as a foreign) language under real-world conditions. According to our results, all considered involved parties are positive about such a mobile learning companion when specific requirements are met. We did not observe any community-related negative impact such as teasing for bad results, for example, and conclude that the considered gamification features such as challenges with classmates and rankings are suitable for the investigated school context. Based on the results, we derive a set of guidelines for the design and development of a mobile learning companion, its introduction in class and its practical usage.

This paper reports on a between-subject, comparative online study of three information visualization demonstrators that each displayed the same dataset by way of an identical scatterplot technique, yet were different in style in terms of visual and interactive embellishment. We validated stylistic adherence and integrity through a separate experiment in which a small cohort of participants assigned our three demonstrators to predefined groups of stylistic examples, after which they described the styles with their own words. From the online study, we discovered significant differences in how participants execute specific interaction operations, and the types of insights that followed from them. However, in spite of significant differences in apparent usability, enjoyability and usefulness between the style demonstrators, no variation was found on the self-reported depth, expert-rated depth, confidence or difficulty of the resulting insights. Three different methods of insight analysis have been applied, revealing how style impacts the creation of insights, ranging from higher-level pattern seeking to a more reflective and interpretative engagement with content, which is what underlies the patterns. As this study only forms the first step in determining how the impact of style in information visualization could be best evaluated, we propose several guidelines and tips on how to gather, compare and categorize insights through an online evaluation study, particularly in terms of analyzing the concise, yet wide variety of insights and observations in a trustworthy and reproducable manner.