Designing Custom Keypads For Real People

When developing equipment, it's easy to get sointo the custom keypads of modern mobile
focused on the engineering that you forget thephones even though the control design makes
people who will be using the machine. The resultlittle sense today.
can be less efficient control systems andDesigners of any equipment need to ask
ill-designed custom keypads.themselves periodically if traditional control
Case In Point: Thumb Size and Textingsystems still make sense. As technology changes,
The May 2008 issue of the Journal of Usabilitycontrol systems need to change with them. Fitting
Studies had an article titled, "A Study of themachinery with custom keypads designed to fit
Effect of Thumb Sizes on Mobile Phone Textingthe needs of the modern user will lead to items
Satisfaction". The authors conducted a study ofwhich are easier to use and more satisfactory to
110 adults texting from their own mobile phones.customers.
It correlated thumb length and circumference withUsability Tests Provide Guidelines
texting satisfaction.Rather than staying with the same old control
The study showed that today's cell phones withsystems, many manufacturers are conducting
their traditional 4x3 key layout are not well suitedtests similar to the one mentioned above to
for texting. As phones and their custom keypadsgauge how effectively end users can operate the
have become smaller, it has become moreequipment. These tests often reveal control
difficult for users to text comfortably. Theproblems that even the users aren't aware of.
authors recommended phone manufacturers useCustomers get used to an old, inefficient system
larger, more widely spaced keys to betterand don't realize there is a better way.
accommodate texting. They also made the radicalNew control systems don't have to mean radical
suggestion that the layout of letters on the keysdesign changes. Small adjustments in control
be changed so more common letters are placedpositioning can make significant differences in ease
on the middle key with the least used lettersof operation. In particular, as electronics become
placed in the right column.smaller there is a realistic limit to how small the
Designing Outside the Boxcontrol panels can become. Interviewing users
Texting is a good example of how an archaicabout their satisfaction with control systems can
control design inhibits modern use. Telephonereveal that custom keypads have become too
keypads were designed for desktop and wallsmall.
mounted phones that were dialed with an indexManufacturers should re-examine control systems
finger rather than by thumb while held in the hand.as a routine part of the design process. Recruiting
The letters themselves are result of theend users to test prototypes allows the company
long-obsolete practice of naming telephonea chance to refine controls and make the
exchanges. These conventions have been carriedequipment more accessible.