1. A method for performing a computer action based on a user input on a touch screen of a computing system, the user input entered by a user by holding the computing system in a right or left hand and touching the touch screen with the other hand, the method comprising the steps of: the computing system receiving the user input on the touch screen of the computing system; the computing system receiving parameters characterizing the user input on the touch screen; the computing system determining which hand is used to enter the user input on the touch screen; the computing system determining the parameters characterizing the user input on the touch screen match predefined parameters corresponding to the hand used to enter the user input and a specific computer action, within a specific error tolerance; and the computing system performing the specific computer action.