# i41CX+ — RPN Calc with Printer and CAS > Advanced RPN scientific calculator with integrated CAS and virtual printer. (iPhone/iPad app by Antonio Lagana.) - Source: https://appshunter.io/ios/app/i41cx-plus/id289068865 (this page in markdown: same URL + `.md`) - Developer: [Antonio Lagana](https://appshunter.io/developer/289068868) - Category: Productivity, Utilities - Price: $24.99 - Rating: 4.80/5 from 104 App Store ratings · 264 written reviews indexed - Age rating: 4+ - Requires: iOS 9.0 · 361 MB - Languages: American English - Released: 2019-02-01 - Data updated: 2026-08-30 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/i41cx-plus/id289068865/reviews.md ## What is i41CX+? i41CX+ is an advanced programmable and expandable RPN scientific calculator with a virtual thermal printer/plotter and workstation-class CAS capabilities that is far beyond a mere replica of the original. In addition to being functionally equivalent to the world-renowned HP-41CX and providing access to its entire library of modules and programs, i41CX+ is enhanced with iOS and hardware features, keyboard overlays, rich set of import and export capabilities, traditional and upbeat diverse set of skins, complete color control, iCloud support, and much more. The i41CX+ CAS is a full implementation of REDUCE. It's like having Mathematica or the computational engine of Wolfram Alpha in your pocket and, best of all, it runs natively so no internet connection is required. The CAS is fully programmable and provides the ability to reuse previous results in computations. Moreover, the CAS has full access to the calculator registers so it is possible to combine RPN programs with CAS programs. This is the finest and most powerful scientific/engineering/financial calculator for iOS devices bar none. CALCULATOR FEATURES: • RPN logic with a 4 element deep memory stack • 319 main and 600 extended memory registers • Over 400 built-in functions, including over 100 functions created specifically for i41CX+ • Time, calendar, alarm, and stopwatch functions • Four module ports provide access to HP-41 expansion pacs • Rich set of functions and algorithms: numerical, mathematical, statistical, complex, matrix, numerical integration, curve fitting, solutions to equations, and much more • Powerful, flexible, and programmable Computer Algebra System (CAS) supporting symbolic, arbitrary precision, scalar, vector and matrix algebra calculations, 2D/3D plotting, and much more • Full-screen text editor with configurable font style and size, color scheme, a user configurable macro keyboard, and a numerical keyboard • 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 - virtually unlimited number of lines • User definable keyboard • Ability to operate the calculator using a Bluetooth keyboard • Device integration: external display mirroring, copy and paste, in-app mail, system keyboard, GPS, accelerometer, digital compass, time and date synchronization, AirPrint, and much more • Virtually unlimited data and program storage capacity using the device's flash memory for local storage • Import/export data, programs, overlays, modules, etc. via the web, email, and iTunes file sharing • iCloud syncing of files and preference settings • iOS 8 Notification Center widget • 43 available keyboard overlays and support for user created overlays • Sound support including synthetic tones and interface sounds • Support for calculator skins and optional mini stack display • Adjustable calculator speed, sound volume, and display colors • Usage & Examples table with usage tips and examples • Quick Reference Guide of all built-in functions • CAS Quick Reference with all built-in functions, operators, switches, and packages • Beautiful and clean user interface PRINTER FEATURES: • Support for printing, plotting, graphics, and special characters • User configurable and programmable print color • Export printer output via email, clipboard, or AirPrint • Ability to save a JPEG image of the paper roll to the device's photo album *********************************************************** A comprehensive FAQ and Mini-Manual are available at http://alsoftiphone.com/i41CXplus. Please don't hesitate to use the "Contact Us" link there if you cannot find the answers or information that you seek. Thank you. ## Key features - RPN logic with 4-element stack - Extensive memory registers - Over 400 built-in functions - Computer Algebra System (CAS) - Virtual thermal printer/plotter - Access to HP-41 module library - Customizable skins and keyboard overlays ## What do users think of i41CX+? Overall sentiment: positive **Pros** - 🚀 Fantastic emulation of the original HP41 calculator - 🔒 Faithful to the original hardware and functionality - 👍 Includes all the expansion modules and accessories - 👍 Responsive and never crashes - 👍 Excellent implementation of RPN and programmability - 👍 Convenient to have a powerful calculator always on hand - 👍 Impressive attention to detail, including keyboard clicks **Cons** - 🔋 Can drain battery when left on - 👎 Small button size can lead to mis-taps - 👎 Slow startup time in some versions **Commonly reported bugs** - Issues with the 41Z math module producing garbled output - Scaling problems with overlays **Most requested features** - Landscape mode for better button size - Haptic feedback for button presses - Ability to load and save programs/modules via cloud/email - Macros or scripting support ## Recent user reviews (10 of 264) All indexed reviews: https://appshunter.io/ios/app/i41cx-plus/id289068865/reviews.md ### 5/5 — HP41 étendue *2026-04-22* Pour les fans d’HP41 et même de la récente DM41X, cette version software comporte des fonctionnalités étendues extraordinaires . Notamment dans le domaine du chargement, déchargement de programmes (et de modules) et leur édition externe. Un outil incontournable pour tous ceux qui travaillent depuis 40 dans l’univers de calcul et de programmation HP41 ### 5/5 — Thank you for this fantastic app! *2026-01-23, version 7.6.17* The HP41 was a breakthrough calculator in its time. I still love it, and the i41CX+ app is a wonderful implementation of this great calc. Worth every penny! ### 5/5 — iOSで動く最高の電卓の一つ *2025-12-02* HP-41Cシリーズには膨大な数のモジュールがあり、このi41CX+で利用することができます。 さらにREDUCEというCASが搭載されているのでモダンな数学用の電卓にもひけを取りません。 iOSで動く最高の電卓の一つだと思います。 ### 5/5 — My goto scientific calc for years *2025-10-21, version 7.6.17* This has been my go to calculator and I find it is the best emulation of the 41CV/CX family. It goes beyond that in many ways from memory to the expanded capabilities. It has always responsive, and has never crashed. Real HP 41 CV an CXs got me through college. Yes that was a long time ago. The access to modules has allowed me to use some of the extended features that made the original so powerful. I was very much into synthetic and Forth programming on the original calculators. I still use some of the programs I wrote in college on this calculator. I wish there was a macOS version of this app. ### 5/5 — MEGA ! *2025-07-16* Diese App bringt den HP-41CX perfekt auf‘s iPhone. Dann kann das gute Museums-Stück in der Vitrine bleiben. Der schnelle Service von AL lässt auch keine Wünsche offen. Großes Dankeschön! GB ### 5/5 — This calculator is amazing *2025-04-21, version 7.6.16* This is the best of the best ! ### 5/5 — Physicist at Large *2025-03-14, version 7.6.16* I cannot rave enough about the i41CX+ app. I have a real hp41CV from college and grad school days (mint condition). I use it rarely so that it doesn't wear out. First HP I owned was a model 67 and I was hooked. This 41cx app keeps the entire 41 product and accessories, and then some, in my pocket. Couldn't be more happy with the performance and user experience. Well done !! Please keep it going. It's bad enough HP has abandon these gems. I'd like to know that this app will remain for years to come. Thanks for the great work. ### 5/5 — Best calculator app. *2025-03-10, version 7.6.16* Worth every penny. I’ve used this almost daily for many years now. Great to see this calculator live on in app form. Thank you Antonio for developing and maintaining this for all these years. ### 5/5 — This is a real good RPN calculator *2024-12-27, version 7.6.16* I was using the HP RPN 41CX calculator since my University days. Miss it so much after it broke down. Finally I found this one on apple App Store about 10 years ago. This one is really really good. I am happy using it everyday for my engineering works. Thanks software developer for this 5 stars app. ### 5/5 — Il miglior calcolatore *2024-12-03, version 7.6.16* Sono un ingegnere e ho usato calcolatrici programmabili dal 1978. Questa è quella che mi è rimasta nel cuore ed è quella che uso ancora oggi, questa app è fantastica! ## Frequently asked questions about i41CX+ ### What does the i41CX+ app do? The i41CX+ app is an advanced programmable RPN scientific calculator that includes workstation-class Computer Algebra System (CAS) capabilities. It functions as a virtual thermal printer/plotter and offers access to an extensive library of modules and programs, enhancing the functionality of the original HP-41CX. ### What are the key features of this calculator app? Key features include RPN logic with a deep memory stack, a large number of memory registers, over 400 built-in functions, a powerful CAS for symbolic calculations, a virtual thermal printer/plotter, and access to the entire HP-41 library of modules and programs. It also supports customizable skins, keyboard overlays, and iCloud syncing. ### How much does the i41CX+ app cost? Based on the provided information, the app is a paid application. There are no mentions of free trials, subscriptions, or in-app purchases, indicating a one-time purchase model. ### What devices is i41CX+ compatible with? The app is designed for iOS devices. It leverages iOS features such as iCloud support, notification center widgets, and integration with system keyboards, Bluetooth keyboards, and external displays. ### Who would benefit from using the i41CX+ app? This app is ideal for users who need a powerful and versatile scientific or engineering calculator. This includes students, scientists, engineers, and financial professionals who require advanced mathematical, statistical, and symbolic computation capabilities, as well as the ability to run legacy HP-41 programs. ## Version history (last 5 releases) ### 7.6.19 — 2026-01-28 • Fixed bug introduced in 7.6.18 ### 7.6.18 — 2026-01-27 • iOS 26 compatibility ### 7.6.17 — 2025-08-20 • Minor bug fixes ### 7.6.16 — 2024-10-06 • Minor bug fix ### 7.6.15 — 2024-04-13 • Minor bug fixes ## Apps similar to i41CX+ | App | Rating | Price | Category | | --- | --- | --- | --- | | [iCalc: Photo Math Calculator](https://appshunter.io/ios/app/icalc-photo-math-calculator/id6448191549) | 4.4 (354) | Free | Productivity | | [Calculator´](https://appshunter.io/ios/app/calculator/id878851717) | 4.6 (465) | Free | Productivity | | [ClevCalc - Calculator](https://appshunter.io/ios/app/clevcalc-calculator/id1221235593) | 4.7 (13,021) | Free | Productivity | | [OneCalc: All-in-one Calculator](https://appshunter.io/ios/app/onecalc-all-in-one-calculator/id1324977193) | 4.6 (5,051) | Free | Productivity | | [OneCalc+ All-in-one Calculator](https://appshunter.io/ios/app/onecalc-plus-all-in-one-calculator/id1324977953) | 4.7 (512) | $3.99 | Productivity | | [Natural Scientific Calculator](https://appshunter.io/ios/app/natural-scientific-calculator/id1221737584) | 4.6 (95) | Free | Productivity | ## More apps by Antonio Lagana - [i41CX](https://appshunter.io/ios/app/i41cx/id292619450) - [iCAS](https://appshunter.io/ios/app/icas/id394637176) All apps by Antonio Lagana: https://appshunter.io/developer/289068868 ## Related topics [sycorp calc](https://appshunter.io/ios/topics/sycorp-calc) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-30.*