TnToolkit
Steven J. Castellucci, Ian Scott MacKenzie · 2009
The pervasive use of ambiguous keypads for mobile text entry necessitates examination of their performance characteristics. This paper presents TnToolkit--a self contained tool to calculate performance measurements for ambiguous keypads. While TnToolkit's focus is ambiguous keypads, it also works with QWERTY and on screen keypads. By default, TnToolkit predicts words per minute performance based on a traditional Fitts' law model, and calculates KSPC, the average keystrokes required to enter each character of text. Existing modules are extensible to implement custom metrics. An experiment reveals that using TnToolkit to gather performance metrics is 69% faster than existing techniques, without compromising accuracy.