An information processing apparatus comprising: a measurement unit which measures an acceleration; a display control unit that displays an object for receiving an instruction of processing on a display screen; a detection unit that detects an operation for the object; and a setting unit that sets a reaction region on the display screen detectable as an operation for the object by the detection unit, wherein the setting unit changes a range of the reaction region according to a magnitude and a direction of an acceleration measured by the measurement unit, wherein when a user touches a position on the display screen as an operation for the object, the setting unit calculates an enlargement ratio α in an x-axis direction and an enlargement ratio β in a y-axis direction of the display screen for subsequent resetting the range of the reaction region by the following expressions: α = Tx + T / Lx ⋅ Ax, β = Ty + T / Ly ⋅ Ay, wherein Tx is the number of x-axis pixels from the touched position to an end point of the object closest to the touched position, Ty is the number of y-axis pixels from the touched position to an end point of the object closest to the touched position, Lx is the number of x-axis pixels of the object closest to the touched position, Ly is the number of y-axis pixels of the object closest to the touched position, Ax is an x-axis component and Ay a y-axis component of the acceleration measured at the time of touching the display screen, and T is a constant value, and the setting unit resets the range of the reaction region of the object closest to the touched position using the calculated enlargement ratio α and the calculated enlargement ratio β, wherein the setting unit calculates the number of pixels increased in the x-axis direction by multiplying the calculated enlargement ratio α, the number of x-axis pixels Lx of the object, and the x-axis component Ax of the acceleration, and wherein the setting unit calculates the number of pixels increased in the y-axis direction by multiplying the calculated enlargement ratio β, the number of y-axis pixels Ly of the object, and the y-axis component Ay of the acceleration. a measurement unit which measures an acceleration; a display control unit that displays an object for receiving an instruction of processing on a display screen; a detection unit that detects an operation for the object; and a setting unit that sets a reaction region on the display screen detectable as an operation for the object by the detection unit, wherein the setting unit changes a range of the reaction region according to a magnitude and a direction of an acceleration measured by the measurement unit, wherein when a user touches a position on the display screen as an operation for the object, the setting unit calculates an enlargement ratio α in an x-axis direction and an enlargement ratio β in a y-axis direction of the display screen for subsequent resetting the range of the reaction region by the following expressions: α = Tx + T / Lx ⋅ Ax, β = Ty + T / Ly ⋅ Ay, wherein Tx is the number of x-axis pixels from the touched position to an end point of the object closest to the touched position, Ty is the number of y-axis pixels from the touched position to an end point of the object closest to the touched position, Lx is the number of x-axis pixels of the object closest to the touched position, Ly is the number of y-axis pixels of the object closest to the touched position, Ax is an x-axis component and Ay a y-axis component of the acceleration measured at the time of touching the display screen, and T is a constant value, and the setting unit resets the range of the reaction region of the object closest to the touched position using the calculated enlargement ratio α and the calculated enlargement ratio β, wherein the setting unit calculates the number of pixels increased in the x-axis direction by multiplying the calculated enlargement ratio α, the number of x-axis pixels Lx of the object, and the x-axis component Ax of the acceleration, and wherein the setting unit calculates the number of pixels increased in the y-axis direction by multiplying the calculated enlargement ratio β, the number of y-axis pixels Ly of the object, and the y-axis component Ay of the acceleration.