Comparison

i41CX vs WP 31s

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

Head to head
About

i41CX

This app offers a powerful RPN scientific calculator experience, functionally equivalent to a renowned model. It provides extensive memory registers, over 300 built-in functions, and programmability. Advanced features can be unlocked via in-app purchases.

Highlights
  • RPN logic with 4-element stack
  • 319 main and 124 extended memory registers
  • Over 300 built-in functions
  • Programmable up to 2000 lines
  • User-definable keyboard
  • Bluetooth keyboard support
  • Device integration 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

WP 31s

This app emulates a classic RPN scientific calculator, offering a rich function set for daily use with a simplified interface. It's based on the more complex WP 34s but is designed for easier operation.

Highlights
  • RPN scientific calculator emulation
  • Rich function set
  • Simplified, less cluttered keyboard
  • Based on WP 34s
  • Available on iOS
Features
Read full description

WP 31s is a classic RPN scientific calculator based on the powerful but more complex WP 34s. Now available on iOS too (see the support site for other emulators and for the real stuff). It is not programmable but has a rich function set for daily use and is easier to use, thanks to a less cluttered keyboard. A manual can be downloaded at http://sourceforge.net/projects/wp34s/files/doc/Manual_wp_31s_1_2q.pdf/download

Screenshots

i41CX4 screens
WP 31s1 screens

Verdict

The call

The clearest difference is price: WP 31s at Free against i41CX's $7.99. WP 31s also leads on in-app purchases (none vs 4) and rating (4.9 vs 4.6). i41CX's advantage is update cadence (every 5 weeks vs every 10 months) and chart position (#182 vs unranked). 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

WP 31s is free to download; i41CX costs $7.99 up front. i41CX sells 4 one-off in-app purchases. WP 31s asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

WP 31s holds the better App Store score, 4.9 against 4.6. Both are backed by a comparable volume of ratings — 45 and 15 respectively. Written reviews point the same way: 90% of i41CX's written reviews are positive against 100% of WP 31s's.

UpkeepUpdate frequency

i41CX ships an update every 5 weeks, WP 31s every 10 months. The most recent releases landed on October 17, 2026 and October 11, 2026 respectively.

Scorecard9 real differences · 2 level
i41CX versus WP 31s: the parameters behind the verdict, then further details
Parameteri41CXWP 31s
Price$7.99Free — better
Rating4.6 (45 ratings)4.9 (15 ratings) — better
Positive reviews90.5% of reviews100.0% of reviews — better
Number of ratings45 — better15
Update frequencyEvery 5 weeks — betterEvery 10 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
Best chart rank#182 — better—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.012.0 — better
Further details — not scored
Size135 MB16 MB
Age rating4+4+
DeveloperAntonio LaganaPascal Meheut

Customer experience

i41CX

All ratings45 ratings
Positive91.1%
Neutral2.2%
Negative6.7%
Written reviews126 reviews
Positive90.5%
Neutral3.2%
Negative6.3%

WP 31s

All ratings15 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews11 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

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

WP 31s

No in-app purchases

Questions

Is i41CX free?
i41CX costs $7.99, and also offers in-app purchases.
Is WP 31s free?
WP 31s is free to download, with no in-app purchases.
Which has better reviews, i41CX or WP 31s?
WP 31s is rated higher. i41CX averages 4.6 out of 5 from 45 ratings, while WP 31s averages 4.9 from 15 ratings.
Do i41CX or WP 31s have ads?
Neither i41CX nor WP 31s shows ads.
Which is updated more often, i41CX or WP 31s?
i41CX ships an update every 5 weeks, and WP 31s every 10 months. Most recently, i41CX was updated on October 17, 2026 and WP 31s on October 11, 2026.

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