Depending on your phone's design, it may offer you multiple ways to enter data and commands, including a physical or virtual touchpad. Each design has pros and cons, and some phones include games and applications that take advantage of touch-screen technologies. Understanding how your phone's input system works can help you master its capabilities and avoid data-entry frustrations.
Traditional
The simplest phone design uses tactile push buttons for alphanumeric input. In this design, the manufacturer aligns a grid of plastic or rubber keys, often in a single-piece mat, over a circuit board with movable metal tabs. When you push one of the buttons, it presses the metal tab into the board, completing the circuit and registering the keypress. While cheap and usually robust, such designs limit your input to predetermined buttons and commands.
Resistive
The widespread adoption of touch screens in cell phones has allowed developers to replace physical buttons with virtual ones. The most basic type of touch screen consists of separate, electrically charged layers that come into contact when you press on a given spot. The phone measures the change in the electric field to identify the area touched, and compares that to the image on the screen to determine which button you pressed and respond. You can use resistive touch screens with gloved hands or a stylus, but they may require significant pressure to operate and are prone to damage.
Capacitive
A capacitive touch screen relies on the electrical field inherent in the human body for tracking touch locations. The phone's screen contains a series of electrodes for monitoring its electrical field, and when you touch the screen with your finger, your body alters that field. The phone measures the change to identify the button touched. Capacitive touch screens allow you to press buttons with a light touch, as well as enter commands by gestures or swiping your fingers lightly across the screen. Such screens require bare skin contact or a specially designed stylus to work properly.
Feedback
As touch screens lack the tactile response of pressing down a physical button, many manufacturers have created technologies to simulate that physical feedback. Some phones produce an audible click or buzz when you press a virtual button, to let you know your contact registered. More advanced models actually include a tiny actuator in the assembly that moves the screen perceptibly with each "click." This tactile feedback can help you avoid data-entry errors, and makes the touch-screen experience more realistic.
Tags: touch screens, touch screen, avoid data-entry, buttons with, electrical field, measures change, phone design