CalcEn is an Android utility and tools application developed by Elisha C. King. It serves as a comprehensive complex number calculator with a user-friendly interface, specifically designed for editing and computing complex mathematical expressions, matrices, and polynomial functions. One of its standout features is the ability to solve complex math problems by capturing a picture, alongside a natural display for editing mathematical expressions, complex functions that accept complex arguments, and computation on the complex plane.

Moreover, CalcEn offers a wide range of functions including logarithmic functions that can accept arguments less than zero, hyperbolic functions and their inverses, and the ability to work with complex numbers in rectangular or polar form. Users can convert complex results between polar and rectangular forms, perform calculations in radians or degrees, and benefit from a historical display of previous calculations. The application also supports complex matrices, element-wise and matrix operations, simplification of functions with real or complex coefficients, and the computation of roots for real or complex functions.