Comparison

MathU RPN Calc vs RLM

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

Head to head
About

MathU RPN Calc

This advanced scientific and financial calculator utilizes the Reverse Polish Notation (RPN) system. It offers over 96 functions, catering to professionals with features for finance, programming, and general scientific calculations. Optimized for iOS devices, it provides a robust and accurate computational experience.

Highlights
  • RPN entry system
  • Over 96 functions
  • Scientific calculations
  • Financial calculations (IRR, NPV, mortgage)
  • Programmer's calculator (HEX, OCT, DEC, BIN)
  • IEEE double precision accuracy
  • Portrait/landscape keypad switching
Features
Currently charting
Read full description

MathU RPN is an advanced scientific and financial calculator designed in the spirit of classic HP calculators. MathU RPN is based on the Reverse Polish Notation (RPN) entry system and combines more than 96 functions to create a calculator that meets the needs of professionals who use a calculator every day. First released in 2008, the calculator continues to be updated with new features as iOS improves. MathU RPN works on the iPhone, iPad and macOS. On the iPad, MathU RPN maintains its orientation as the iPad is turned and you can rotate it from portrait to landscape keypad layout via the Rotate button. When the iPad has a hardware keyboard attached, you can type of the names of the buttons the keyboard to execute them -- thus avoiding having to press the calculator keys with your finger. On the iPhone, you can lock it to always use the portrait or landscape keypad or let it switch orientations automatically when you rotate your phone. MathU RPN is an excellent financial calculator. There are functions for computing mortgage amortization and cash flow computations like IRR and NPV, as well as functions for working with dates. Many of the existing financial functions have been extended to handle odd periods (conforming to the same conventions as the HP-12C). In addition, on tall devices (like most iPhones), the financial registers are displayed on the keypad. MathU RPN is also a programmer's calculator. The A-F keys are available right up front for easy entry in HEX mode and there are many functions for working with integers. Dr. Clay M. Thompson of Creative Creek has harnessed the computational power of the iPhone to produce an accurate and high performance calculator. General Features - IEEE double precision accuracy (16 digits) - High performance fast computations - 20 storage registers - 5 financial registers - 16 high stack (switchable to 4) - Supports international number separators - Switch between portrait and landscape keypads - Quick access to the preference and on-line manual - Stack and Register view (accessible via [RCL][RCL] Scientific Features - Full set of trigonometric functions - Full set of logarithmic and power functions - Statistics functions - Polar and rectangular conversions - Repeated computations Mortgage and Loan Features - Time value of Money functions - Compute mortgage and loan terms - Solve for payments and interest rates - Solve for IRR and NPV - Date functions Computer Science Features - Number bases (HEX, OCT, DEC, BIN) - Bitwise logical operations - Masking and shifting functions - Support for a wordsizes up to 48 bits - Modular arithmetic MathU 4.1 supports iOS 16.6 or higher as well as macOS. For more info (including the users manual) go to http://www.creativecreek.com or use the built-in quick reference.

About

RLM

Features
Read full description

The RLM-14BX application is a financial and business calculator. It is based in the Hewlett-Packard HP-14B calculator, but specially designed to bring up the most of your iOS devices and , at the same time, conserving the easy of use and all the functions originally provided by the real calculator and nine menus added to expand it to professional level. Get it for free during 30 days (after you have to buy an In-App-Purchase lifetime payment). The RLM-14BX has a extensive Menu System accessed from the Main Menu or directly from the keyboard: >Main Menu: •Bond Price & Yield: Calculates the Price, Yield and Effective Duration of a Bond. •Call / Put: Black-Scholes Options Valuation Model to Calculates the CALL, PUT and “Greeks” values. •Depreciation: Calculates depreciation with SL, SOYD, DB or MACRS methods and conventions. •Date / Time: Calculates days between dates with Actual, 360 or 365 days calendars and time intervals between different times. •Currencies: world currencies conversions with manual input or on-line current rates. •Units Convert: Customizable physical units conversions. •Solver: Calculates arbitrary equations entered as text expression to solve any of the variables knowing the others. •Probability: Combinations, permutations and Normal, Exponential, t-Student and Weibull probability distributions. •Utilities: -General Settings: Customize many aspects of the calculator including formats & feedbacks. -Storage Registers: Store and perform operations directly over the calculators storage registers. -Memory Content: Clear, Back-Up or Restore part or all of the Calculator's memory. -Help Documents: Description and examples of all the calculator worksheets and features. -Solver Equation: Algebraic expression for use in the "Solver" worksheet. -Units Database: Customize the "Units" worksheet. >Keyboard Menus: •AMORT: Loan Amortization Schedule for a single or several loan payments. •CFLO: Cash Flows calculation of the NPV, IRR, NFV, NUS, Payback Period, etc. for different cash flows occurring at regular time intervals. •STAT: Statistics calculation of the Mean, Median, Standard Deviation, Curve Fitting and forecasting, etc. for two variables data samples. •MATH: Trigonometric and logarithmic functions. •B.EVEN: Break-Even analysis using the relation: Profit = (Price - Var.Cost) • Units - Fix.Cost •ROI: Return on Investment analysis using the relation: ROI% = Revenue • %Profit / Investment •INVEN: Inventory turnover analysis using the relation: Inventory Turnover = 2 • Cost of Goods Sold / (Begin - End inventory) >Keyboard direct functions: •Interest Rates Conversion: NOM%-EFF%-P for Nominal and effective interest conversion. •Percents Change: OLD-NEW-%CHG for percent change calculations. •Percent Total: TOTAL-PART-%TOTAL for percent total calculations. •Business Margin: CST-PRC-MAR for business margin calculations. •Time Value of Money (TVM): N-I/YR-PV-PMT-FV for compound interest calculations. System requirements: iOS 15.0 or above. 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

MathU RPN Calc4 screens
RLM4 screens

Verdict

The call

The clearest difference is price: RLM at Free against MathU RPN Calc's $24.99. RLM also leads on update cadence (every 4 days vs every 6 weeks). MathU RPN Calc's advantage is in-app purchases (none vs 1) and chart position (#136 vs unranked). On ads, device support and iOS requirement 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; MathU RPN Calc costs $24.99 up front. RLM sells 1 one-off in-app purchase. MathU RPN Calc asks for nothing beyond the download.

UpkeepUpdate frequency

MathU RPN Calc ships an update every 6 weeks, RLM every 4 days. The most recent releases landed on October 31, 2026 and November 4, 2026 respectively.

Scorecard4 real differences · 7 level
MathU RPN Calc versus RLM: the parameters behind the verdict, then further details
ParameterMathU RPN CalcRLM
Price$24.99Free — better
Rating5.0 (149 ratings) — better—
Positive reviews92.5% of reviews—
Number of ratings149 — better—
Update frequencyEvery 6 weeksEvery 4 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
Best chart rank#136 — better—
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS16.615.0 — better
Further details — not scored
Size8 MB3 MB
Age rating4+4+
DeveloperCreative Creek, LLCR.L.M. Software

In-app purchases

None

MathU RPN Calc

No in-app purchases

1 purchases

RLM

One-time1
  • Lifetime Purchase$9.99

Questions

Is MathU RPN Calc free?
MathU RPN Calc costs $24.99, with no in-app purchases.
Is RLM free?
RLM is free to download, with in-app purchases available.
Do MathU RPN Calc or RLM have ads?
Neither MathU RPN Calc nor RLM shows ads.
Which is updated more often, MathU RPN Calc or RLM?
MathU RPN Calc ships an update every 6 weeks, and RLM every 4 days. Most recently, MathU RPN Calc was updated on October 31, 2026 and RLM on November 4, 2026.

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