The common handheld mobile phone offers only about 12 keys on in its keypad, whereas all languages have many more characters. English has 26 and Indian languages typically have 60 or more characters that form part of the popular usage. Supporting the input of scripts on the phone has been a challenge and many different approaches have been explored for decades. One familiar approach is called multitap where several taps on a key is used to type a character. Other more intelligent approach has included a dictionary on the phone estimating the word from user inputs. These have had their advantages and disadvantages. The Indian language is even more complex to support due to the nature of the language and the above approaches have remained unsuitable. A familiar handicap with the dictionary based system of the past was the inability to support non dictionary words — names of people and places which occur so commonly in the nature of communication done on SMS.
CleverTexting is a new Texting Technology that predicts letters as you type. It is based on the statistical nature of a language and is dictionary less. Along with a user interface innovation of dynamic key assignment, it offers a terrific advantage of single keystroke typing on limited keypad devices like the mobile phone; and offers a smoother typing experience to the user.
When the common phone is held in the right hand, all the keys of the phone are not equally accessible to the texting thumb. The key 1 would be the most accessible and the key # would be the least comfortable. Although the common phone is used by far more number of people in the world than the PC keypad, the phone keypad has not witnessed any redesign based on ergonomic considerations. You will see that the current English keypad on the phone just lays out the characters in their alphabetic order. It's called the ITUT keypad. Since the characters are dynamically allocated in CleverTexting depending on their conditional probabilities, they are also shown on the screen according to their ergonomic ranks. Hence you would be most often pressing on keys which are most comfortable to the thumb. The character arrangements can be changed when the phone is used on the left hand.
Our languages are highly statistically correlated. In the Figure below it can be seen that in the English language, of the half a million possible four letter combinations, only about 1% make up 90% of all occurrences. The statistical curve is the same for all languages of the world and hence CleverTexting works for all languages of the world. It is the high statistical correlation which has offered great advantage to this strategy over the previous dictionary based approaches.
The usability of CleverTexting is not only restricted to the mobile phone but is applicable for all kinds of digital interfaces. It can be used in the PC1web to write in any Indian language. It can also be used by Set Top Boxes and in IPTV for offering a simple usability to type on the TV from the remote of the TV. It can be used in an ATM because that too is a limited keypad device with the same interface. And it can be used in touchscreen kiosks, vending machines etc.
There are several variations of CleverTexting which are available:
Ergonomic: The most likely next characters are arranged to positions easiest for the thumb, as in Right hand and left.
Ergonomic and Persistent: Alphabets retain their positions between two state transitions. This reduces jitter and improves searchability of characters.
Legacy Keypad: Heavy users of legacy keypad habitually look for keys there. In this implementation, alphabets are assigned legacy positions as best as possible. An extension of legacy, alphabets that could not be assigned legacy positions are shown highlighted to improve searchability.
Nearest Key: The next likely keys crowd around the last used key.
