SpeedCrunch is described as «free, fast, high precision open source algebraic calculator with an intuitive interface and many features, such as variables, syntax highlighting, functions, persistent input history & more» and is a very popular Calculator in the education & reference category. There are more than 100 alternatives to SpeedCrunch for a variety of platforms, including Android, Mac, Windows, Online / Web-based and iPad. The best alternative is Qalculate!, which is both free and Open Source. Other great apps like SpeedCrunch are fxSolver, Numi, Windows Calculator and Google Calculator.
