Unipad: single stroke text entry with language-based acceleration

ABSTRACT

A stylus-based text entry technique called Unipad is presented. Unipad combines single-stroke text input with language-based acceleration techniques, including word completion, suffix completion, and frequent word prompting. In a study with ten participants, entry rates averaged 11.6 wpm with 0.90% errors after two hours of practice. In follow-on sessions to establish the expert potential, four users entered "the quick brown fox" phrase repeatedly for four blocks of 15 minutes each. Average rates on the last block ranged from 17.1 to 35.1 wpm, with peak rates reaching 48 wpm.

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.5 INFORMATION INTERFACES AND PRESENTATION (I.7)
      H.5.2 User Interfaces (D.2.2, H.1.2, I.3.6)

Keywords:
mobile text entry, stylus input, word completion, word prediction