Calcbot is described as 'simple and beautifully designed calculator for your iPhone, iPod touch and iPad. You’ll never open the built-in Calculator app again' and is a Calculator in the education & reference category. There are more than 50 alternatives to Calcbot for a variety of platforms, including Windows, Android, Mac, Online / Web-based and iPhone. The best alternative is SpeedCrunch, which is both free and Open Source. Other great apps like Calcbot are Qalculate!, Windows Calculator, Numi and Google Calculator.
SpeedCrunch is a 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.
Qalculate! is a 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).
A simple yet powerful calculator that includes standard, scientific, and programmer modes, as well as a unit converter. It's the perfect tool to add up a bill, convert measurements in a recipe or other project, or complete complex math, algebra, or geometry problems.
Soulver is a smart notepad with a built-in calculator. It gives instant answers to any calculations it finds in your text. It's a better way to work stuff out than with a traditional calculator, and a more lightweight tool for quick calculations than a spreadsheet.
CalcTape is a revolutionary new kind of pocket calculator. With CalcTape, also extensive calculations remain clearly structured. CalcTape makes the arithmetic process visible - you can generate intermediate results and subsequently correct or change all numbers and operations.