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TapCalculator: nonvisual touchscreen calculator for visually impaired people preliminary user study

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Abstract

TapCalculator is a novel, non-visual touchscreen calculator that uses simple gestures to represent digits and operations with the support of audio feedback and is designed specifically for visually impaired users. It enables users to do basic calculations without visually locating buttons on a screen or having to know braille or learning complex coding for digits. It uses a series of tapping and swiping to perform arithmetic operations. This paper lays the groundwork for devising, improving, and implementing intuitive, user-friendly application to meet the needs of individuals with visual impairments. This paper is supported by primary-source research conducted by the author, including a review of several touchscreen calculators, using a small sample of visually impaired users. Seven participants were asked to compare the TapCalculator to two other virtual calculators, BrailleTap and TalkBack. From this preliminary usability study, quantitative findings indicate that blind users enter digits and arithmetic operations on the TapCalculator faster and less power consumption than the others due to TapCalcultator’s emphasis on directional gestures and allows users to tap with a maximum of 5 fingers. BrailleTap was shown to be more accurate than both TapCalculator and TalkBack, suggesting areas for improvement and further study. Through interviews with participants, qualitative results suggest that, for blind users attuned to braille, directional gestures are more accessible than locating the position of a touchscreen button. This paper suggests improvements to enhance the user experience of the TapCalculator, which is still in its infancy, and other virtual calculators for the visually impaired users.

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Notes

  1. Total error rate (TER) is the rate of error occurred while typing equations including numbers, operations, and the equal sign.

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Acknowledgements

I would like to thank all participants from Taif University accessibility center for devoting their time and effort in the study.

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Correspondence to Mrim Alnfiai.

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Alnfiai, M. TapCalculator: nonvisual touchscreen calculator for visually impaired people preliminary user study. J Multimodal User Interfaces 16, 143–154 (2022). https://doi.org/10.1007/s12193-021-00379-7

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