  From carrying grocery bags to holding onto handles on the bus, there are a
variety of situations where one or both hands are busy, hindering the vision of
ubiquitous interaction with technology. Voice commands, as a popular hands-free
alternative, struggle with ambient noise and privacy issues. As an alternative
approach, research explored movements of various body parts (e.g., head, arms)
as input modalities, with foot-based techniques proving particularly suitable
for hands-free interaction. Whereas previous research only considered the
movement of the foot as a whole, in this work, we argue that our toes offer
further degrees of freedom that can be leveraged for interaction. To explore
the viability of toe-based interaction, we contribute the results of a
controlled experiment with 18 participants assessing the impact of five factors
on the accuracy, efficiency and user experience of such interfaces. Based on
the findings, we provide design recommendations for future toe-based
interfaces.
