RPN-32 CE — The first photo-realistic HP-32E simulator for the iPhone

Version 1.5

RPN-32 CE is a photo-realistic simulation of Hewlett-Packard's third-generation scientific calculator HP-32E.

Released in July 1978, the HP-32E was the mid-range scientific member of the so-called "Spice" series. It was discontinued in 1983.

RPN-32 CE is a massively enhanced, yet fully compatible version of the HP-32E. Unlike the original, it's also programmable.



Tap the wrench symbol or double-tap the display to access the
settings screen:

iPhone 6 Screenshot:



Version History

1.5 – Feb 27, 2017
  • New:
  • New commands:
      ABS (Absolute value of x)
      NOP (No Operation)
      RAND (Random number)
      CSTK (Clear stack)
  • • Full complement of compare operations (12 in total)
  • • Improved FRAC function
  • • Pause length changed from 2 secs to 1 sec
  • • Import and run programs created on the HP-25 simulator GO-25

  • Bug Fix:
  • • Pasting a GTO command into the display could crash RPN-32
  • • RND didn't round correctly certain values in SCI and ENG mode

1.4 – Oct 2, 2016
  • New:
  • • Calculator sounds mix with background audio and have their own volume control
  • • Now with 30 sample programs included

1.3 – July 26, 2016
  • New:
  • • Pause activity is shown in main and register view
  • • Improved results for SIN, COS, TAN with very large arguments
  • • Decimal addition/subtraction for higher precision

1.2 – June 3, 2016
  • New:
  • • Added comparisons with zero (tap and drag finger into keyboard area before releasing)
  • • Register view gets updated while a program is running
  • • Run/stop and single-step program without leaving register view
  • • Added copy of actual display to register view
  • • LastX may be used in register arithmetic operations, e.g. RCL + yˣ
  • • Tapping any key stops program execution
  • • SST and BST may be cancelled by dragging finger off key
  • • Shared programs include calculator settings and registers
  • • Improved handling of values pasted as text
  • • Improved address correction when deleting program steps
  • • Support for uncommon number groupings (e.g. India)
  • • Added copy of R/S key in bottom-right corner for easy access even when programming keys are turned off

  • Bug Fixes:
  • • Fixed x < y and x > y comparison functions involving very large numbers
  • • Fixed automatic target correction of GTO command at end of program memory
  • • Fixed rounding in SCI mode
  • • Entering too many digits was not properly handled

1.1 – March 22, 2016
  • New:
  • • Registers, display format and angular mode are saved with programs
  • • Program loading sets display format and angular mode
  • • Registers may be preset by pasting multi-line text into the display
  • • Current program step is shown below display. Tap to show or hide.
  • • In program mode, progress bar shows fill status of program memory
  • • User programs are listed separatedly from sample programs

  • Bug Fixes:
  • • Automatic stack-lift was not re-enabled in certain situations
  • • Large arguments of tanh(x) could cause a crash
  • • GTO 83 was not programmable

1.0 – February 18, 2016
  • First public version.


RPN-32 CE is available here:




Get RPN-32 CE and its sister app RPN-38 CX at a bargain:

The Spice Pac


Copyright © 2017. All rights reserved.
Apple and the Apple logo are trademarks of Apple Inc., registered in the U.S. and other countries. iPad is a trademark of Apple Inc.