Why does a mobile telephone have a keypad?
Automatic dialing technology is about eighty years old [23]; before that, calls were switched by an operator at a switchboard, who physically connected trunk lines to make the circuit. Mechanical automation obsolesced the operator, and the rapid advance of computerized switching systems in the 1960s gave birth to DTMF “touch tone” dialing.[24] It is this “touch tone” keypad which we have come to consider as the “natural” interface to the telephone, even though it is not quite as old as this author. In the years before the microprocessor revolution, when AT&T stamped out hundreds of millions of absolutely identical, identically dumb, touch-tone telephone handsets, users had to peck the number into the keyboard every single time they placed a call. How often do you hand tap a number into your mobile phone? I’ve been doing some informal polling, and the answer seems to be, “About once a week.” Although we might be using our mobile phone tens of hours a week, we only tap a number into it o
