Direct from the US Patent Office comes Swipe Gestures for Touch Screen Keyboards. Authored by former Fingerworks founder Wayne Westerman for Apple, the latest patent details some very useful (and practical) additions to the iPhone's on screen keyboard, to provide quick access to common keys:
For example, erasing and basic punctuation insertion, directional
swipes (also referred to herein as "swipe gestures") over the
alphabetic keys can be used as an alternative to striking certain keys.
Because the Space and Backspace keys are quite frequently used, they
are logical candidates for the rightward and leftward swipes,
respectively. Leftward and rightward swipes intuitively match the
cursor travel caused by these symbols. Following this cursor movement
analogy, the Enter/Return may be invoked by a downward swipe, and a
Shift/Caps may be invoked by an upward swipe. Alternatively, as the
Enter and Shift functions may be less frequently invoked, these may be
substituted for other functions as well. One alternative mapping for
the upward swipe, for example, could be to activate an alternative
numeric and punctuation keypad or a particular punctuation symbol like
an apostrophe or period.
The hope is that these optional functions could provide advanced users with many useful
shortcuts while not steepening the learning curve for novice users.