iPhone 3G

Like many of the newer SmartPhones, the iPhone 3G uses "capacitive touch screen" technology. Without getting overly technical, this basically means that it reacts to the electrical conductivity of the human finger, so a plain plastic stylus will not work. Styluses have to be specifically designed to mimic a human finger, making it necessary that they be made at lease a certain size and of only particular materials, as with those below.