Comparison

RPNu vs Constructive Calculator

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

Head to head
About

RPNu

Features
Read full description

RPNu is a calculator that makes crunching numbers easier than it’s algebraic equivalent. RPN stand for Reverse Polish Notation (The ‘u’ stands for universal, meaning it runs on both the iPad and iPhone.) and is the numeric evaluation method used for this app. RPN, I feel, is far superior to the algebraic method and once learned you will never want to use the algebraic again. This calculator has all the normal mathematical function, but also contains a host of other functions that you may find very useful. Space is limited in this description but here are the highlights: Help: There is extensive help to aid the user in determining how to use this app. It is also context sensitive. Programable: You can write your own programs and there are many tools to aid you in doing this. Graphics: You can graph equations and there are several modes to cover almost all requirements. A universal converter that you will find very useful. Matrix arithmetic (determinate, invert, add, subtract and multiply). Date calculator and an hours calculator with moon phase display. Elements and periodic table information. Combinations and permutations calculator Equation integration and root finder. Amortization with many useful functions. Mapping function that allows you to determine distance between points and other functions. Hyperbolic functions. Hexadecimal, Octal, and Binary modes. Barometer function showing QNE and QNH. A compass that not only shows magnetic and true north, but also shows the address you are at. This app includes extensive support for a Bluetooth keyboard. Also, extensive support is given to export your calculations to either email or the universal clipboard.

About

Constructive Calculator

This calculator performs calculations with arbitrary precision, avoiding rounding errors common in standard calculators. It provides an extensive scientific keypad and can display an unlimited number of digits for exact results.

Highlights
  • Arbitrary-precision calculations
  • Unlimited digit display
  • Scientific keypad
  • Exact results for large numbers
  • Running tape of calculations
  • Locale-aware digit grouping
Features
Read full description

Ordinary calculators round. Constructive Calculator doesn't. It computes with constructive real numbers, an arbitrary-precision engine that keeps every result exact and hands you as many correct digits as you ask for. The rounding errors that quietly accumulate in ordinary calculators simply never happen. AS MANY DIGITS AS YOU WANT A pocket calculator stops at about 15 digits and rounds off the rest. Constructive Calculator keeps every result exact, so the digits a normal calculator throws away are still there. Swipe √2, π, or any answer to pull in tens, hundreds, or thousands more, computed on demand. SCIENTIFIC KEYPAD Trigonometry in degrees or radians and their inverses, exponentials and logarithms, powers and roots, factorials, percentages, the constants π and e, and the standard normal distribution, its CDF Φ and quantile Φ⁻¹, computed to the same arbitrary precision as everything else. BIG INTEGERS, IN FULL 52! (the number of ways to shuffle a deck) prints in full, all 68 of its digits, with no scientific-notation hand-waving. BUILT FOR CLARITY A running tape of recent calculations, locale-aware digit grouping, and copy at whatever precision you need. Constructive Calculator is an independent port of Hans Boehm's constructive-reals calculator, rebuilt natively for iPhone and iPad.

Screenshots

RPNu4 screens
Constructive Calculator4 screens

Verdict

The call

The clearest difference is update cadence: Constructive Calculator at every 8 days against RPNu's every 2 months. RPNu's advantage is device support (3 vs 1). On price, ads, in-app purchases 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

RPNu ships an update every 2 months, Constructive Calculator every 8 days. The most recent releases landed on October 12, 2026 and October 21, 2026 respectively.

Scorecard2 real differences · 7 level
RPNu versus Constructive Calculator: the parameters behind the verdict, then further details
ParameterRPNuConstructive Calculator
PriceFreeFree
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 2 monthsEvery 8 days — better
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.0 — better16.0
Further details — not scored
Size49 MB1 MB
Age rating4+4+
DeveloperScott JohnsonDmitriy Mayorov

In-app purchases

None

RPNu

No in-app purchases

None

Constructive Calculator

No in-app purchases

Questions

Is RPNu free?
RPNu is free to download, with no in-app purchases.
Is Constructive Calculator free?
Constructive Calculator is free to download, with no in-app purchases.
Do RPNu or Constructive Calculator have ads?
Neither RPNu nor Constructive Calculator shows ads.
Which is updated more often, RPNu or Constructive Calculator?
RPNu ships an update every 2 months, and Constructive Calculator every 8 days. Most recently, RPNu was updated on October 12, 2026 and Constructive Calculator on October 21, 2026.

Other comparisons