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Retro 15C

Retro 15C

by Greg Hewgill

212 ratings
113 reviews
📚 Education
🔧 Utilities
Free

Details

  • Released
  • Updated
  • December 15, 2012
  • April 27, 2017

Features

Developer

Greg Hewgill
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Retro 15C screenshot #1 for iPhone
Retro 15C screenshot #2 for iPhone
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❓4 answered
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About

This app emulates a classic RPN scientific calculator, offering advanced features like complex number arithmetic, matrix calculations, and programmability. It provides a functional and complex tool reminiscent of 1980s calculators.

✓Complex number arithmetic
✓Matrix calculations
✓Numerical root finder
✓Numerical integration
✓Statistical functions
✓Programmable
Show original description

What users say

Summarized from real user reviews of Retro 15C. Based on 212 reviews and a 4.3/5 average, it highlights the 7 positives and 5 negatives reviewers mention most about this Utilities app.

Positive things

  • 🚀Lightning-fast calculator
  • 👍Authentic look and feel of HP 15C
  • 🚀Faster than real HP 15C
  • 👍Excellent RPN emulation
  • 👍Familiar interface for HP 15C users
  • 👍Great representation of original calculator
  • 👍Obvious labor of love by developer

Negative things

  • 🐛Doesn't save settings, programs, or memory
  • 🐛No key press feedback or sound
  • 🐛Blinking display issue with large calculations
  • 🐛Bugs with HMS conversions
  • 🐛Can't close app on newer iPhones
See all reviews

What's New in Retro 15C

1.1

April 27, 2017

This app has been updated by Apple to display the Apple Watch app icon. Updated 64 bit build that will survive long past the next iOS update. Also, the calculator display now scales correctly for all iPhone screen sizes. The name of the app has been changed to "Retro 15C". It's still free and always will be. Thank you for your support!

More

User reviews

Most RecentHighest RatedLowest Rated

Outstanding program

The designers/coders sweat the details. The appearance of the calculator is identical to the physical calculator. Excellent work !!!
neeknameneekname

iPhone 17

It’s apparently not possible to close the screen, or close the app on the iPhone 27, which has virtual handles on the screen corners. You must turn off the screen and then switch. Thanks for your support.
I hope you can fix this, as I have enjoyed the app for many years.
Olemax IIOlemax II

Bad app

Locks my iPhone in landscape mode, next to impossible to exit app
vince from MDvince from MD

An old friend

I was delighted to find this. I still own, and use, both 40 year old 15C and 12C calculators I acquired working at the HP IC fab that made chips for them. Thanks for bringing the 15C to my iPhone!
tonymaxftonymaxf

Good, but no way out

As far as a HP11, it’s fine. But, there is no exit button, half swipe up app switcher fails also
BLTomiBLTomi
See 108 more reviews

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User experience

🐞

Reported Bugs

4 issues

Blinking display with large calculations

Bug

Bugs with HMS conversions

Bug

Inability to close app on newer iPhones

Bug

Stopped working with iOS 14 updates

Bug
✨

Requested Features

5 requests

Add haptic feedback on key presses

Feature

Implement continuous memory to save settings and programs

Feature

Add portrait mode option

Feature

Improve compatibility with newer iOS versions

Feature

Add copy/paste functionality for stack and registers

Feature

FAQ

What does the Retro 15C app do?

The Retro 15C app emulates a classic RPN (Reverse Polish Notation) scientific calculator. It offers a wide range of advanced mathematical functions, including complex number arithmetic, matrix calculations, numerical root finding, and integration.

What are the key features of this calculator app?

Key features include complex number arithmetic and trig functions, matrix calculations, a numerical root finder, numerical integration, statistical functions with linear regression, and full programmability. It aims to replicate the functionality of classic 1980s RPN calculators.

Is this app free to use?

Yes, the Retro 15C app is completely free to use. The developer has stated there are no ads or extra in-app purchases, making it a free offering.

Who is the target audience for this app?

This app is designed for students and scientists who remember or appreciate the functionality of classic RPN scientific calculators from the 1980s. It appeals to users who value a balance between functionality and complexity in their calculation tools.