1. An input apparatus, comprising: a display unit for displaying a screen composed of a plurality of layers including a first layer for displaying at least one input area and a second layer for displaying at least one input area, wherein the second layer is different from the first layer; a touch panel arranged in association with the display unit and for detecting an input to the input area displayed on the display unit; an input mode determination unit for determining an input mode to the touch panel; a superimposed area input detection unit for detecting an input to a superimposed area where the input area displayed on the first layer and the input area displayed on the second layer are superimposed; and an input control unit for processing, in a case where the superimposed area input detection unit detects an input to a superimposed area where the input area displayed on the first layer and the input area displayed on the second layer are superimposed, the input as an input to the input area displayed on the first layer when the input is determined as an input of a first input mode by the input mode determination unit, and the input as an input to the input area displayed on the second layer when the input is determined as an input of a second input mode by the input mode determination unit.