The features of this app are;
- simple four arithmetic operations are provided
- up to 10 calculation formula are displayed
- displayed computation can be utilized as input

You cannot do complicated calculation, but it can be done by repeating simple calculation.

For instance, 1+2x(3+4)=15

1: 3+4=7
2: 7x2=14
3: 14+1=15

The computation of 1: can be used as input of 2:. The computation of 2: can be used as input of 3:.

For instance, when you buy some goods with different prices and need to calculate the total amount.

1: 198x3=594
2: 245x2=490
3: 98x4=392
4: 594+490+392=1476

This can be done by calculator with memory function.
The key operation may be like following; () shows displayed numbers.

"198" "x" "3" "=" "M+" (594)
"245" "x" "2" "=" "M+" (490)
"98" "x" "4" "=" "M+" (392)
"MR" (1476)

Have you ever pushed incorrect buttons by mistaken when you use "M+" and/or "MR" button? I often do it, and re-start calculation from first.

If you use this app, the key operation is like follows;

"198" "x" "3" "=" (198x3=594)
"245" "x" "2" "=" (245x2=490)
"98" "x" "4" "=" (98x4=392)
Touch 1: "+" Touch 2: "+" Touch 3: "=" (594+490+392=1476)

Instead of using "M+", just touching displayed calculation formula becomes input. This may be easier operation with less mistake.

The design of this app is very simple.
Three (3) background images, which are Gray, Siver and Gold, are selectable by clicking "i" icon shown at top-right of the display.

Up to 10 calculation formula are displayed, and over 10 will overwright from first one. Please be advised all memoried numbers and formula will be erased by closing this app.

The following is explanation of clear function buttons.

AC　clear all displayed numbers and formula
MC　clear just one formula which is in the middle of calculation
CE　clear input numbers

Number of digits you can use in this app is up to that iPhone allows. When length of numbers and/or formula exceed length of each display area, a part of them will be omitted.