MK61+ – Programmable RPN Calculator for iPhone

The MK61+ application is a programmable RPN calculator, based on the Electronika MK 61 calculator, that was produced in 80-90s of the last century.

This is not an exact emulator of it yet. The goal is to get a handy tool to use on daily basis. So, some extra functionality was added, that was absent in the original MK 61 calculator, and some its quircks were fixed.

The main calculator features are the following:

  • Authentic look and feel.
  • Good balance between powerful features and simplicity of use.
  • Quick State¹ panel to get easy insight into calculator's state.
  • The rich help system including Quick Help² and Calculator Guide.
  • Ability to save and load and e-mail programs and data.
  • Support for input and output operations on data files.
  • Operating stack with 5 registers and 15 indexed registers to store intermediate results.
  • Program memory with 160 cells, that is more than enough for most practical tasks.
  • Rich set of instructions including ones for subroutine calls, jumps, loops and their indirect counter-parts.
  • Support for hexadecimal and binary numbers.³
  • Copy-paste operations with a quick tap on the calculator display.
  • ¹ To show Quick State panel swipe to bottom on the display.
  • ² To get Quick Help for a button, switch, or the display tap it with finger and hold for ~3 seconds.
  • ³ Hexadecimal and binary numbers can contain up to 10 digits.

Calculator's Main View

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