Comparison

RPN vs RLM

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

Head to head
About

RPN

Experience a faithful simulation of the groundbreaking HP-65 programmable calculator on your iPhone. This app offers virtual program and data cards, a paper tape printer, and a robust card manager. Explore four distinct operating modes, including an enhanced "Super-65" option.

Highlights
  • Virtual program and data cards
  • Virtual paper tape printer with AirPrint
  • Database-driven card manager
  • Create, delete, and organize unlimited cards
  • Sharing via email, AirDrop, Dropbox, iTunes
  • Paste and run existing HP-65 listings
  • Four distinct operating modes
Features
Read full description

World's first pocket computer! Now running on your iPhone. RPN-65 SD is the iPhone version of RPN-65 Pro, the first complete simulation of Hewlett-Packard's stunning HP-65 programmable calculator for iOS. Produced from 1974 to 1977 at an initial price of $795 (that's close to $5,000 today!), the HP-65 was a breakthrough. Not only was it programmable, it also contained a motorized magnetic card reader - and still fit into Bill Hewlett's shirt pocket. Experience this revolutionary calculator on your iPhone. With over 180 original HP programs included with the app, you can get started right away. "A work of art. Fantastic!" (MacBreak Weekly, episode 572) Features: • Virtual program and data cards • Virtual 2000-line paper tape printer supports AirPrint • Powerful database-driven card manager • Create, delete, label, and organize a virtually unlimited number of cards • Sharing: e-mail, AirDrop, Dropbox, iTunes, copy, paste, print • Paste existing HP-65 listings into RPN-65 and run them • "Live" display of stack, memory registers, program counter, flags • Reads program and data cards created by RPN-65 Pro • Reads data cards created by RPN-67 Pro/SD and RPN-97 Pro Run RPN-65 SD in any of 4 modes: 1 - Just like the original HP-65 2 - Like the original HP-65, but at much higher speed 3 - With many user-interface improvements, like backstep key or jump to any program step 4 - "Super-65" with 999 program steps, 120 labels, 120 registers, nested subroutines, and much more For details, free program downloads, calculator handbook and much more, visit the RPN-65 website: cuveesoft.ch/rpn65

About

RLM

This advanced scientific calculator emulates the functionality of the HP-15C, offering comprehensive tools for finance, business, statistics, and scientific calculations. It supports programming, equation solving, and unit conversions, optimized for iOS devices.

Highlights
  • Programmable advanced scientific calculator
  • Finance and business calculation menus
  • Statistics and probability functions
  • Complex numbers and matrix operations
  • Unit and currency conversions
  • Equation solver and programming capabilities
Features
Read full description

The RLM-15CX application is a programable advanced scientific calculator. It is based in the Hewlett-Packard HP-15C calculator, but specially designed to bring up the most of your iOS devices and , at the same time, conserving the easy of use and the functionality originally provided by the real calculator. >Finance Menu: •Account Balance: Credit line type account based on cash transactions and interest rates applied. •Amortization: Loan Amortization Schedule for a single loan payment or from several payments at once. •Bond Price & Yield: Bonds calculations in an easy way with all options and values at sight. •Black-Scholes Options: CALL, PUT and “Greeks” calculations of the Black-Scholes European option valuation model. •Equal Periods Cash Flows: Solve problems where different cash flows occur at regular time intervals. •Unequal Periods Cash Flows: Solve problems where different cash flows occur at different dates. •Depreciation: Calculates depreciation with SL, SOYD, DB or MACRS methods and conventions. values at sight. •Interest Rates: Nominal and effective interest conversion. •Time Value of Money: Compound Interest problems involving money earning interest over a period of time. >Business Menu: •Bill-Tip-Split: Calculates the sharing of a Bill with Tip. •Break-Even: Analyze the following relation: Profit = (Price - Var.Cost) • Units - Fix.Cost •Currency Exchange with on-line rates. •Percents & Margins: Calculates %Change, %Total and Business margins. >Date / Time Menu: Calculates Date and Time intervals with all values at sight. >Statistics Menu: •One-Variable Statistics: Calculations for one variable data samples. •Two-Variable Statistics: Calculations for two variables data samples. •Curve Fitting: 6 Regression models to fit a curve based on two variables data samples. •Probability: Combinations, permutations, Normal, Exponential, t-Student and Weibull probability distributions. >Scientific Menu: •Complex Numbers: Operations and functions with complex numbers. •Matrix: view, create or edit matrices with real or complex elements. •Plane Triangle: Solves a two dimensional triangle (ASA,SAS,SSA and SSS). •Spherical Triangle: Solves a triangle in a sphere’s surface (AAA,AAS,ASA,SAS,SSA and SSS). •Universal Constants: All the NIST-CODATA fundamental physical constants. •Vectors 3D: Operations and functions with vectors in Cartesian, Spherical or Cylindrical coordinates. >Convert Menu: •Angles & Polar: Convert angles between DEG,RAD,GRAD,DMS or Slope % & Polar-Rectangular coordinates. •Currencies: world currencies conversions with manual input or on-line current rates. •Interest Rates: Nominal and effective interest conversion. •Units: Physical units conversions. >Program Menu: Create, edit or load previously saved programs. >Solver Menu: Solve arbitrary algebraic equations entered and saved in the equation editor and creates a menu with all the variables to solve any of them. >Utilities Menu: •General Settings: Customize the calculator to your preference. •Memory Content: Shows all memory content edit, backup or restore. •Help Documents: learn by example about all menus. >Editors: submenu to select data editors. System requirements: iOS 15.0 or above. 30 days Free-Trial. In-App-Purchase: One-Payment for life. License Agreement: http://www.apple.com/legal/itunes/appstore/dev/stdeula Disclaimer: THIS IS NOT A HEWLETT PACKARD CALCULATOR, AND IS NOT SPONSORED IN ANYWAY BY HEWLETT PACKARD OR ANY OF ITS SUBSIDIARIES

Screenshots

RPN4 screens
RLM4 screens

Verdict

The call

The clearest difference is price: RLM at Free against RPN's $2.99. RLM also leads on update cadence (monthly vs every 4 months). RPN's advantage is rating (5.0 vs 4.1) and in-app purchases (none vs 4). On ratings volume, 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

RLM is free to download; RPN costs $2.99 up front. RLM sells 4 in-app purchases, starting at $0.49 per month. RPN asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

RPN holds the better App Store score, 5.0 against 4.1. Both are backed by a comparable volume of ratings — 8 and 18 respectively. Written reviews point the same way: 100% of RPN's written reviews are positive against 80% of RLM's.

UpkeepUpdate frequency

RPN ships an update every 4 months, RLM monthly. The most recent releases landed on November 2, 2026 and October 30, 2026 respectively.

Scorecard8 real differences · 3 level
RPN versus RLM: the parameters behind the verdict, then further details
ParameterRPNRLM
Price$2.99Free — better
Rating5.0 (8 ratings) — better4.1 (18 ratings)
Positive reviews100.0% of reviews — better80.0% of reviews
Number of ratings818 — better
Update frequencyEvery 4 monthsMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
Best chart rank#174 — better—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.0 — better15.0
Further details — not scored
Size62 MB6 MB
Age rating4+4+
DeveloperCuVee SoftwareR.L.M. Software

Customer experience

RPN

All ratings8 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

RLM

All ratings18 ratings
Positive72.2%
Neutral11.1%
Negative16.7%
Written reviews15 reviews
Positive80.0%
Neutral13.3%
Negative6.7%

In-app purchases

None

RPN

No in-app purchases

4 purchases

RLM

Subscriptions3
  • Monthly Subscription$0.491 Month
  • Semi-Annual Subscription$2.996 Months
  • Annual Subscription$5.991 Year
One-time1
  • One-Time Purchase$9.99

Questions

Is RPN free?
RPN costs $2.99, with no in-app purchases.
Is RLM free?
RLM is free to download, with in-app purchases available.
Which has better reviews, RPN or RLM?
RPN is rated higher. RPN averages 5.0 out of 5 from 8 ratings, while RLM averages 4.1 from 18 ratings.
Do RPN or RLM have ads?
Neither RPN nor RLM shows ads.
Which is updated more often, RPN or RLM?
RPN ships an update every 4 months, and RLM monthly. Most recently, RPN was updated on November 2, 2026 and RLM on October 30, 2026.

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