Cell phones like Google’s Nexus One, iPhone, Nokia N8, HTC Droid, BlackBerry Storm and tablets like the iPad have a capacitive touch screen. That means the screen will only respond to touch commands from human fingers and not the stylus pen that may have come with your old PDA.

There’s a small problem though.

Your fingers are great for navigation or for typing on the capacitive touch screen but when it comes to handwriting recognition or painting, you are likely to find a stylus pen as a more natural and accurate medium for input than the fat finger tips.