A terminal apparatus comprising: an input interface configured to receive an input of an operation performed by a user; and processing circuitry that implements an input detection section that outputs an operation signal in accordance with contents of the operation in response to the operation being detected on the input interface, an operation determination section that determines whether the operation by the user is a short press operation or a long press operation based on a time in which the input detection section outputs the operation signal before lift-off of the finger of the user, whereby when a press operation is regarded as the short press operation a function that is assigned to the short press operation is executed and a corresponding screen associated to this first function is displayed, and when a press operation is regarded as the long press operation, a function that is assigned to the long press operation is executed and a corresponding screen associated to this second function is displayed, wherein a display processing section is configured to display a preview screen on a display device showing the contents of the screen associated with the function that is assigned to the long press operation, the preview screen being displayed when the press of the finger is continued until after a time period that the operation determination section associates with the short press operation wherein the display processing section is configured to display the preview screen along with the screen which was displayed when the user started the press operation, wherein the display processing section progressively increases a size of the preview screen as a function of time. an input interface configured to receive an input of an operation performed by a user; and processing circuitry that implements an input detection section that outputs an operation signal in accordance with contents of the operation in response to the operation being detected on the input interface, an operation determination section that determines whether the operation by the user is a short press operation or a long press operation based on a time in which the input detection section outputs the operation signal before lift-off of the finger of the user, whereby when a press operation is regarded as the short press operation a function that is assigned to the short press operation is executed and a corresponding screen associated to this first function is displayed, and when a press operation is regarded as the long press operation, a function that is assigned to the long press operation is executed and a corresponding screen associated to this second function is displayed, wherein a display processing section is configured to display a preview screen on a display device showing the contents of the screen associated with the function that is assigned to the long press operation, the preview screen being displayed when the press of the finger is continued until after a time period that the operation determination section associates with the short press operation wherein the display processing section is configured to display the preview screen along with the screen which was displayed when the user started the press operation, wherein the display processing section progressively increases a size of the preview screen as a function of time.