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Designers spend more resources to develop better mobile experiences today than ever before. Researchers commonly use visual search efficiency as a usability measure to determine the time or effort it takes someone to perform a task. Previous research has shown that a computational visual saliency model can predict attentional deployment in stationary desktop displays. Designers can use this salience awareness to co-locate important task information with higher salience regions. Research has shown that placing targets in higher salience regions in this way improves interface efficiency. However, researchers have not tested the model in key mobile technology design dimensions such as small displays and touch screens. In two studies, we examined the influence of saliency in a mobile application interface. In the first study, we explored a saliency model's ability to predict fixations in small mobile interfaces at three different display sizes under free-viewing conditions. In the second study, we examined the influence that visual saliency had on search efficiency while participants completed a directed search for either an interface element associated with high or low salience. We recorded reaction time to touch the targeted element on the tablet. We experimentally blocked high and low saliency interactions and subjectively measured cognitive workload. We found that a saliency model predicted fixations. In the search task, participants found highly salient targets about 900 milliseconds faster than low salient targets. Interestingly, participants did not perceive a lighter cognitive workload associated with the increase in search efficiency. [ABSTRACT FROM AUTHOR]

Graphical authentication schemes offer a more memorable alternative to alphanumeric passwords. However, they have been criticized for being susceptible to over-the-shoulder attacks (OSA). To solve this shortcoming, schemes have specifically been designed to be resistant to OSA. Common strategies used to decrease the ease of OSAs are grouping targets among distractors, translating them to another location, disguising the appearance of targets, and using gaze-based input. We are the first to provide a direct comparison of the common strategies regarding usability and OSA resistance. Specifically, we examined three OSA resistant graphical schemes, an eye tracker scheme, and a traditional alphanumeric password. To capture usability performance, we measured login times, learnability, memorability, satisfaction, acceptability, and error rates. OSA performance was examined to determine the relative resistance of each scheme. We found that graphical schemes are memorable after three weeks, and they were resistant to OSAs. Login time was acceptable for some schemes and not others. Learnability and satisfaction were disappointing, and error rates were high likely due to the novelty of these graphical schemes. Alphanumeric passwords offer the best learnability. [ABSTRACT FROM AUTHOR]