Method and apparatus for zooming picture and switching played contents of handheld electronic device

A method for zooming a picture of a handheld electronic device, comprising: acquiring a first slide touch input applied to a side touch screen of a handheld electronic device (S301); determining a direction of the first slide touch input (S302); and zooming in or out a picture, displayed on a display screen of the handheld electronic device, according to the direction of the first slide touch input (S303).