8+ similar apps compared and reviewed
Whether you want more options like r.Calc or a completely different take on the same concept, our curated list of 8+ similar apps has you covered. Updated for 2026 with the latest ratings and comparisons.
This utility app functions as a Reverse Polish Notation calculator. It handles complex numbers and utilizes extended precision for all calculations, offering an unlimited stack depth and an undo feature for up to 10 operations.
This educational calculator promotes the use of Base Twelve (duodecimal) in math and science. It offers standard mathematical functions in both duodecimal and decimal modes, with automatic conversion between them. It utilizes Reverse Polish Notation (RPN) for calculations.
This advanced scientific calculator simulates the classic HP-42S RPN calculator with enhanced features. It offers algebraic expressions, unit conversions, directories for storage, a larger resizable display, financial functions, and 2D plotting with integral and root finding.
This scientific calculator utilizes a four-level stack and natively handles complex numbers. It allows users to input and view numbers in both polar and rectangular formats, remembering its state and offering 10 memory locations.
This app faithfully recreates the 1975 HP-21 pocket scientific calculator, offering RPN functionality and a full suite of mathematical, trigonometric, and logarithmic functions. It features a 10-digit LED display, stack and storage registers, and a keystroke log for detailed operation tracking.
This app offers a powerful scientific and engineering calculator with advanced features like programmability, multiple number bases, and statistical functions. It emulates the functionality of calculators from the 70s and 80s, providing over 100 functions for complex calculations.
