Calca is an incredible new calculator for OS X and iOS. “Calculator,” though, is not the proper description; it’s a text editor that allows you to declare variables and do live calculations with it.
What a good idea, and something that should have been obvious before. It’s like writing out calculations on paper by hand, except the calculations happen live.
You’ve got to use it. It’s dramatically more useful than a normal calculator application or spreadsheet for most purposes we use them for. It makes using them laughable when you can use this.
Calca is one of my favorite new applications. Go get it.