Daily UI Challenge 004

Day 4 of the Daily UI Challenge: The Calculator.

Let's reinvent the calculator!
First of all, do we need an equal sign? When we're typing "2 + 14" for example, it seems useless to have to ask the app "show the result". Now we can see the result on the go while typing just the numbers and operators.
So I decide to remove this sign in my design.

Then we have more space. We can let the blank for a bigger screen area or add functionality which will be useful in everyday life.
I ask myself: When are you using your calculator ?".
- When I want to know how much my friends owe me or the more often when I go shopping.
You must see what I'm talking about. You see a nice jacket on sale, 30%! But at that moment you have to calculate how much is it 30% for the jacket price then retrieve this amount. Not less than 2 steps.

Could we have just a mode which will do that operation like simple addition or subtraction?
I designed it too! Take a look at the demonstration and please leave a comment or just like this shots to tell me if you want this feature.