Optimizing a Personalized Cellphone Keypad

  • Joonseok Lee
  • Bob McKay
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6935)


Current layouts for alphabetic input on mobile phone keypads are 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.

We optimize for two-thumb use, minimizing the number of strokes, and consecutive use of the same key or the same hand. Using these criteria, the algorithm re-arranges the characters on a 10-key pad. We demonstrate that this arrangement can generate a more effective layout, especially for SMS-style messages. Substantial savings are verified by computational analysis.


Keypad layout adaptive optimized personalized multigram 


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  1. 1.
    Altman, A.: Why air travel is about to get worse. Time Magazine (October 2009),,8599,1929324,00.html
  2. 2.
    Jong, K.A.D.: Evolutionary Computation. MIT Press, Cambridge (2006)zbMATHGoogle Scholar
  3. 3.
    Gong, J., Tarasewich, P.: Alphabetically constrained keypad designs for text entry on mobile devices. In: CHI 2005: Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, pp. 211–220. ACM, New York (2005)Google Scholar
  4. 4.
    How, Y., Kan, M.-y.: Optimizing predictive text entry for short message service on mobile phones. In: Human Computer Interfaces International (HCII 2005), Las Vegas (2005),
  5. 5.
    Lesher, G., Moulton, B., Higginbotham, D.: Optimal character arrangements for ambiguous keyboards. IEEE Transactions on Rehabilitation Engineering 6(4), 415–423 (1998)CrossRefGoogle Scholar
  6. 6.
    Moradi, S., Nickabadi, A.: Optimization of mobile phone keypad layout via genetic algorithm. In: Information and Communication Technologies, ICTTA 2006, 2nd edn., vol. 1, pp. 1676–1681 (2006)Google Scholar
  7. 7.
    Nesbat, S.B.: A system for fast, full-text entry for small electronic devices. In: ICMI 2003: Proceedings of the 5th International Conference on Multimodal Interfaces, pp. 4–11. ACM, New York (2003)Google Scholar
  8. 8.
    Pham, T., Kim, K., McKay, B., Nguyen, X.H.: An adaptive, personalised chording keyboard. In: 2009 Korean Human-Computer Interface Conference, pp. 245–252. The HCI Society of Korea (February 2009)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Joonseok Lee
    • 1
  • Bob McKay
    • 2
  1. 1.SMLV Lab, College of ComputingGeorgia TechAtlantaUSA
  2. 2.SC Lab, Comp. Sci. and Eng.Seoul National UniversitySeoulKorea

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