Hapinasu1 on 26 April 2009
Well let's get some things straight. There are many different types of touch screens. Three common ones are Pressure, Heat, and Electricity.
A pressure touchscreen recognizes pressure on the touchscreen. (I'm pretty sure the DS uses this)
A heat touchscreen recognizes heat from your fingers. (I'm pretty sure most phones use this)
And an electric touchscreen recognizes the electric current from your fingers. (iPhone uses this)
That grease problem might just be grease/sweat from your face/hands. ^^
