Optimizing a Personalized Multigram Cellphone Keypad

TL;DR

This paper introduces a genetic algorithm to personalize cellphone keypad layouts by optimizing for individual text history, reducing typing effort through multigrams and ergonomic considerations, validated by computational and human tests.

Contribution

It presents a novel genetic algorithm approach for customizing cellphone keypads with multigrams, improving efficiency over standard layouts.

Findings

Significant reduction in typing strokes for personalized layouts.

Enhanced efficiency in SMS-style message input.

Validated improvements through computational and human evaluations.

Abstract

Current layouts for alphabetic input on mobile phone keypads are very inefficient. We propose a genetic algorithm (GA) to find a suitable keypad layout for each user, based on their personal text history. It incorporates codes for frequent multigrams, which may be directly input. This greatly reduces the average number of strokes required for typing. We optimize for two-handed use, the left thumb covering the leftmost rows and vice versa. The GA mini- mizes the number of strokes, consecutive use of the same key, and consecutive use of the same hand. Using these criteria, the algorithm re-arranges the 26 alphabetic characters, plus 14 additional multigrams, on the 10-key pad. We demonstrate that this arrangement can generate a more effective layout, especially for SMS-style messages. Substantial savings are verified by both computational analysis and human evaluation.