App: Formules Desktop
Developer: Christophe Lestrade
Genres: Utilities, Education

Engineers, scientists, and students often need to perform calculations that are difficult to enter on a calculator. If the calculations involve various formulas, with the need to test various input values, a programming language is appropriate, but source code will never be as intuitive as well-rendered mathematics for designing a formula.
 
With Formulas create beautifully rendered formulas and evaluate them!

You can use real and boolean expressions. 

Formulas can be used in other formulas.

On each document, you can define a set of inputs that are used to populate your formulas with values.

The main features are:

-Easily create complex formulas and save them for later use.
-Use as many formulas as necessary.
-Undo/Redo support.
-Change the value of your inputs with immediate results updating.
-Formules documents created on a Mac can be used with the iPad and iPhone versions

Release notes:
It is possible to add new parameters to a function when this function is already used.
Various interface improvements.