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Ng, Alexander; Brewster, Stephen; Williamson, John (2014)
Languages: English
Types: Other
In this paper, we investigate the effects of encumbrance (carrying typical objects such as shopping bags during interaction) and walking on target acquisition on a touchscreen mobile phone. Users often hold objects and use mobile devices at the same time and we examined the impact encumbrance has on one- and two- handed interactions. Three common input postures were evaluated: two-handed index finger, one-handed preferred thumb and two-handed both thumbs, to assess the effects on performance of carrying a bag in each hand while walking. The results showed a significant decrease in targeting performance when users were encumbered. For example, input accuracy dropped to 48.1% for targeting with the index finger when encumbered, while targeting error using the preferred thumb to input was 4.2mm, an increase of 40% compared to unencumbered input. We also introduce a new method to evaluate the user's preferred walking speed when interacting - PWS&I, and suggest future studies should use this to get a more accurate measure of the user's input performance.
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

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