Opening the iTunes Store.If iTunes doesn't open, click the iTunes application icon in your Dock or on your Windows desktop.Progress Indicator
Opening the iBooks Store.If iBooks doesn't open, click the iBooks app in your Dock.Progress Indicator

iTunes is the world's easiest way to organize and add to your digital media collection.

We are unable to find iTunes on your computer. To buy and download i41CX — RPN Calculator by Antonio Lagana, get iTunes now.

Already have iTunes? Click I Have iTunes to open it now.

I Have iTunes Free Download
iTunes for Mac + PC

i41CX — RPN Calculator

By Antonio Lagana

Open iTunes to buy and download apps.


i41CX is the same powerful advanced programmable RPN scientific calculator as the highly acclaimed i41CX+ but without the latter’s incredibly advanced capabilities such as the printer, expansion, CAS, etc. It is functionally equivalent to the world-renowned HP-41CX and inherits all of the i41CX+ usability features including extremely responsive and animated key clicks, audible key feedback sounds, optimally spaced keys for accurate input, traditional and upbeat modern diverse set of skins, etc.

If you are looking for a powerful programmable RPN scientific calculator but don’t need all of the capabilities of i41CX+ then i41CX is for you. And best of all, if you ever decide that you need the more advanced capabilities of i41CX+ you can enable them using secure in-app purchases right within the app!

• RPN logic with a 4 element deep memory stack
• 319 main and 124 extended memory registers
• Over 300 built-in functions, including nearly 100 functions created specifically for i41CX
• Time, calendar, alarm, and stopwatch functions
• Rich set of functions and algorithms: numerical, mathematical, statistical, and much more
• Access to the entire HP-41 library of solutions for science, mathematics, statistics, engineering, business, financial, surveying, medicine, real estate, and many other domains
• Programmable - Over 2000 lines
• User definable keyboard
• Ability to operate the calculator using a Bluetooth keyboard
• Device integration: external display mirroring, copy and paste, GPS, accelerometer, digital compass, time and date synchronization, and much more
• iOS 8 Notification Center widget
• Sound support including synthetic tones and interface sounds
• Support for calculator skins and optional mini stack display
• Adjustable sound volume and display colors
• Usage & Examples table with usage tips and examples
• Quick reference guide of all built-in functions
• Beautiful and clean user interface

A comprehensive FAQ is available at Please don't hesitate to use the "Contact Us" link there if you cannot find the answers or information that you seek. Thank you.

What's New in Version 7.3.4

### In-App Purchase Upgrade Changes ###
[i41CX+ Features Upgrade and Printer Upgrade]

• Fixed NEWROLL bug that could cause loss of printer output under certain conditions.


iPhone Screenshot 1
iPhone Screenshot 2
iPhone Screenshot 3
iPhone Screenshot 4
iPhone Screenshot 5
iPad Screenshot 1
iPad Screenshot 2
iPad Screenshot 3
iPad Screenshot 4
iPad Screenshot 5

Customer Reviews

Magnificent Emulation

With real programmability like the original (now nearly 40-years old), you should have little difficulty transitioning to the iPhone version. Fish out the original manual if you're rusty (it isn't supplied), and yes, you can upgrade in-app for the emulated plug-in packs (nothing to download, as they are already built-in, awaiting payment).


I bought an HP-41 for the first time in 1981. Still have it. It was the best calculator money could buy (and it was expensive!). This app works EXACTLY like my physical HP-41. The attention to detail is incredible. I was thrilled when I found this app and gladly paid for it.

Nice app for die-hard HP calculator people

Having lost my HP 22, 19C, 45 calculators, this app is a perfect app and love it! RPN habits are engraved in my brain and love this app!

i41CX — RPN Calculator
View in iTunes
This app is designed for both iPhone and iPad
  • $7.99
  • Category: Productivity
  • Updated:
  • Version: 7.3.4
  • Size: 174 MB
  • Language: English
  • Seller:

Compatibility: Requires iOS 5.1.1 or later. Compatible with iPhone, iPad, and iPod touch.

Customer Ratings

We have not received enough ratings to display an average for the current version of this application.
All Versions:

Top In-App Purchases

  1. i41CX+ Features Upgrade$17.99
  2. Overlays Upgrade$2.99
  3. Printer Upgrade$3.99
  4. CAS Upgrade$7.99