When touch screens first appeared, on mobile devices, they needed a special device, such as a stylus, to make effective use of them, however more recent devices can get by with finger touch alone (grease marks excepted of course). There are two types of touch screen commonly in use on mobile devices, these are capacitive and resistive touch screens and choosing the right one for you can make a huge difference to your mobile interactive experience.

Resistive Touch Screen

A resistive touch screen often requires a little bit of pressure to get the screen to respond, this is because it is made up of layers that make a connection when slight pressure is applied. Resistive screens can usually be operated with any number of suitable devices including stylus and fingers. Resistive screens can be designed to detect pressure sensitivity, such as a light or hard press and have been said to be more accurate on small size displays however, due to their multi-layer nature, they may suffer from reflection issues in direct sunlight.

Devices that utilise a resistive touch screen include HTC Tattoo, Nokia N900, and the LG Viewty.

Capacitive Touch Screen

A capacitive touch screen can sense differences in the the local electrical field when something conductive, such as a finger, rests upon it. This can be through the use of an electricity conducting material that is coated on the screen. As such, a slight press is not required making way for gesture based and multi-touch interactivity (though you might struggle to use one whilst wearing a pair of gloves!). Detecting changes in pressure is tricky for capacitive touch screens as it is often simply just active or not active.

Devices that utilise a capacitive touch screen include the Palm Pre, Apple iPhone, Blackberry Storm and the HTC Hero.