NumWorks - The graphing calculator that makes learning math easier.

Numi App - Numi is a beautiful text calculator for Mac.

Rule of 3 Calculator - Apply the mathematical Rule of Three in an easier, faster and more practical way!

Soulver - Soulver is a software application that functions as a calculator that allows you type a continuous stream of information rather than having to input data into multiple cells.

eMathHelp.net - Site is created to help people learn math. Includes algebra, calculus, differential equation calculators and notes with many examples.

Soulver 3 for Mac - A smart notepad with a built in calculator