Qalculate! is described as «multi-purpose cross-platform desktop calculator. It is simple to use but provides power and versatility normally reserved for complicated math packages, as well as useful tools for everyday needs (such as currency conversion and percent calculation)» and is a popular Calculator in the education & reference category. There are more than 50 alternatives to Qalculate! for a variety of platforms, including Mac, Linux, Android, Windows and Online / Web-based. The best alternative is SpeedCrunch, which is both free and Open Source. Other great apps like Qalculate! are fxSolver, Numi, OpalCalc and Google Calculator.
