Keypad for large letter-set languages and small touchscreen devices (case study

Composing Urdu is a thorny task on touch-screen devices particularly handheld modern devices such as smart phones and PDAs. Design and development of optimal keypad for Urdu composing is complicated due to its relatively large letter-set. Conventional QWERTY replica keypad has migrated from computers to small screen devices. The multi-tap T9 keypads are also in use. These have raised grave issues in composing Urdu text on small touch-screen devices. Last but not the least, health concerns have been ignored in development of input systems for Urdu and other languages with large letter-sets. We developed a novel keypad for Urdu that has been optimized for accurate, easy, speedy and efficient typing on small touch-screen handheld gadgets. We carefully designed our proposed keypad so that it offers better visibility, usability, extendibility, aesthetics and user friendliness. We also took the users ’ health issues into account at the design time of our suggested keypad. The evaluation through applying automated procedures, our proposed keypad showed improvement by 52.62 % over the existing keypads. In addition to automated procedures, we carried out the users evaluation for real world performance comparison between our proposed keypad and in-the-market generic keypads. Our proposed keypad is optimized for Urdu. However it is applicable to Arabic, Persian, Punjabi and other Perso-Arabic script languages. With minor changes in the backend script settings, our proposed keypad is applicable to non-Perso-Arabic script languages with larger letter-sets e.g. Hindi etc