The button is large, and the display of the figure is also large.

It is easy to input of the touch pad because the button is large. Moreover, it is easy for a bright environment such as the outdoors to see the content of the screen in a big character and a bright arrangement of color.

It is sounded that the key pushed.

The operator of this calculator is calculated in order putting it like a calculator of Windows . The answer is nine if it pushes in order of 1+2*3. (The calculator of iphone and MacOSX is calculated in consideration of the priority of operator. It is 7 if it pushes in order of 1+2*3)