Comparison

i41CX vs RPN

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

i41CX

This advanced programmable RPN scientific calculator offers a powerful set of functions and a user-friendly interface. It emulates the functionality of a renowned calculator, with options to unlock advanced features through in-app purchases.

Highlights
  • RPN logic with 4-element stack
  • Over 300 built-in functions
  • Programmable up to 2000 lines
  • User-definable keyboard
  • Bluetooth keyboard support
  • Device integration features
  • Customizable skins and display
Features
Read full description

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! FEATURES: • 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 http://alsoftiphone.com/i41CX. Please don't hesitate to use the "Contact Us" link there if you cannot find the answers or information that you seek. Thank you.

About

RPN

This app is a photo-realistic simulation of a classic scientific calculator, offering advanced programming capabilities beyond the original model. It includes a comprehensive set of mathematical functions and features for easy program management and sharing.

Highlights
  • Photo-realistic calculator simulation
  • Fully programmable with 99 steps
  • Extensive scientific and statistical functions
  • Program library and sharing options
  • Import and export programs
  • 44 pre-installed programs
Features
Read full description

RPN-32 CE is the first photo-realistic simulation of Hewlett-Packard's popular mid-range scientific calculator HP-32E for the iPhone. Produced from 1978 through 1983, it was the "Thyme" member of the third-generation HP calculators known as the "Spice" series. While the simulator works like the original calculator, a number of carefully designed extensions make it a lot easier to use. Unlike the HP-32E, this version is fully programmable, running virtually all programs written for the HP-25! Features: • Photo-realistic look-and-feel • Programmable (99 steps), subroutines, flags, loop control, branching • Insert and delete steps with automatic address correction • 20 registers, "continuous", with unrestricted store/recall arithmetic • Indirect register addressing • "Live" register view • Program listing view • Program library view • Store and retrieve any number of programs • Sharing: e-mail, AirDrop, Dropbox, copy, paste, print • 44 programs pre-installed • Import GO-25 programs • Export programs to RPN-25 CE Calculator functions: • Statistics (mean, standard deviation, linear regression, normal distribution) • Factorial • Trigonometric functions (degrees, radians, grads) • Polar/rectangular conversions • Hyperbolics • Inverse, square root, logarithm, exponential, pi • Storage arithmetic (store and recall) • Percent change • Percentage of Total • Unit and hours conversions • Many additional functions not found on the HP-32 Details: cuveesoft.ch/rpn32

Screenshots

i41CX4 screens
RPN4 screens

Verdict

The call

The clearest difference is in-app purchases: RPN at none against i41CX's 4. RPN also leads on price ($1.99 vs $7.99) and rating (5.0 vs 4.7). i41CX's advantage is update cadence (every 3 days vs every 3 months) and review sentiment (90% vs 80%). On ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

i41CX costs $7.99 and RPN $1.99 up front. i41CX sells 4 one-off in-app purchases. RPN asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

RPN holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: i41CX has 47 ratings behind it against 9, so its average is the more settled of the two. Written reviews complicate that: 90% of i41CX's written reviews are positive against 80% of RPN's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

i41CX ships an update every 3 days, RPN every 3 months. Both last shipped on November 10, 2026.

Scorecard8 real differences · 2 level
i41CX versus RPN: the parameters behind the verdict, then further details
Parameteri41CXRPN
Price$7.99$1.99 — better
Rating4.7 (47 ratings)5.0 (9 ratings) — better
Positive reviews90.5% of reviews — better80.0% of reviews
Number of ratings47 — better9
Update frequencyEvery 3 days — betterEvery 3 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.012.0 — better
Further details — not scored
Size135 MB14 MB
Age rating4+4+
DeveloperAntonio LaganaCuVee Software

Customer experience

i41CX

All ratings47 ratings
Positive91.5%
Neutral2.1%
Negative6.4%
Written reviews126 reviews
Positive90.5%
Neutral3.2%
Negative6.3%

RPN

All ratings9 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews5 reviews
Positive80.0%
Neutral0.0%
Negative20.0%

In-app purchases

4 purchases

i41CX

One-time4
  • Overlays Upgrade$2.99
  • Printer Upgrade$3.99
  • CAS Upgrade$7.99
Show 1 more
  • i41CX+ Features Upgrade$17.99
None

RPN

No in-app purchases

Questions

Is i41CX free?
i41CX costs $7.99, and also offers in-app purchases.
Is RPN free?
RPN costs $1.99, with no in-app purchases.
Which has better reviews, i41CX or RPN?
RPN is rated higher. i41CX averages 4.7 out of 5 from 47 ratings, while RPN averages 5.0 from 9 ratings.
Do i41CX or RPN have ads?
Neither i41CX nor RPN shows ads.
Which is updated more often, i41CX or RPN?
i41CX ships an update every 3 days, and RPN every 3 months. Most recently, i41CX was updated on November 10, 2026 and RPN on November 10, 2026.

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