June 27, 2007 Fitts’ Law and the iPhone Keyboard
In Apple’s [video overview][1] of the new iPhone’s softscreen keyboard, the company revealed an interesting feature: by using predictive text algorithms, the phone not only offers suggestions for the words you type, but it also subtly changes each key’s clickable area based on the letters it anticipates you’ll click next. For example, if you’re spelling the word _time_ and begin typing _T-I-M…_, the iPhone checks its dictionary for possible words you might intend to type, and it enlarges the clickable area of the letter likely to occur next (in this case the letter _E)_ even letting _E’s_ target area encroach into the surrounding letters on the keyboard (_W_ and _R)_, if those keys aren’t part of the word.
Not only is this feature a savvy way to make typing on the slick, on-screen keyboard a little easier, it’s an excellent application of [Fitt’s law][2].
[1]: http://www.apple.com/iphone/usingiphone/keyboard_large.html “Apple’s video overview of the new iPhone keyboard”
[2]: http://en.wikipedia.org/wiki/Fitts%27_law “Fitts’ Law on Wikipedia”