Comparison

RPN vs CalcBoard

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

Head to head
About

RPN

Features
Read full description

The basic four function calculator displays numbers in fixed format. The scientific calculator has 75 built-in functions covering logarithms, powers, roots, trigonometric, date, time, memory operations, statistics, and probabilities and up to four user defined macro functions. It displays numbers in user configurable fixed, scientific, or engineering formats. The user configurable calculator has sixteen user configurable function buttons that can each be assigned two functions from 75 built-in functions and access an unlimited number of user defined macro functions. It displays numbers in user configurable fixed, scientific, or engineering formats. The programmer’s calculator has a hexadecimal keypad and displays numbers in user configurable hexadecimal format. It has four basic mathematics, six bitwise, and two shift functions. All calculators share an operation history display for ease of reviewing computations and extensive in-app help documentation. Numbers can be copied to and pasted from the clipboard for ease of use with other applications.

About

CalcBoard

Perform multiple calculations simultaneously on one screen, compare prices side-by-side, and access various modes like scientific and programmer. This ad-free utility offers precise results and stores your data locally.

Highlights
  • Multiple independent calculator panels
  • Side-by-side price comparison
  • Scientific, programmer, and unit converter modes
  • Visible expression history
  • Shared value tray for chaining calculations
  • Named variables for complex formulas
  • Ad-free and no tracking
Features
Read full description

CalcBoard is a calculator with no ads, no subscriptions, and no tracking. Compare prices side by side, run multiple calculations at once, and get precise results — without a single pop-up interrupting your math. NO ADS. NO SUBSCRIPTIONS. EVER. CalcBoard will never interrupt your calculations with pop-ups, banners, or full-screen ads. Premium features are available through a single one-time purchase — no monthly charges, no recurring fees. COMPARE PRICES SIDE BY SIDE Shopping for the best deal? Open two calculators on the same screen and compare unit prices, discounts, or totals without switching back and forth. CalcBoard is the fastest way to figure out which option actually saves you money. MULTIPLE CALCULATORS, ONE SCREEN Run up to eight independent calculator panels simultaneously. Compare prices, check homework, run different scenarios, or calculate tips for a split bill — all without losing your place. SEE YOUR WORK Every expression stays visible as you type — no more guessing what you entered. Every calculation is saved automatically; bookmark and label the important ones, and with Premium search your full history and export it to CSV. FOUR POWERFUL MODES • Basic — Clean, fast arithmetic for everyday math • Scientific — Trig, logs, exponents, and advanced functions • Programmer — Hex, binary, octal, and decimal shown at the same time, with bitwise operations • Unit Converter — 79 units across 10 categories: length, mass, temperature, area, speed, time, data, volume, energy, pressure SHARED VALUE TRAY Push any result to the shared value tray and pull it into another panel. Chain calculations across panels without retyping numbers. NAMED VARIABLES Type tax=0.0825 once, then use price*tax in any panel. Your variables persist between sessions and work in every calculator mode. INSTANT ACCESS FROM CONTROL CENTER (iOS) Add CalcBoard to your iPhone's Control Center and launch it in a single tap from any screen — no hunting through your home screen. Open Settings → Control Center to add the CalcBoard control. PRECISE RESULTS CalcBoard uses arbitrary-precision decimal arithmetic. No floating-point rounding errors. 0.1 + 0.2 = 0.3, exactly. YOUR DATA STAYS ON YOUR DEVICE No ad SDKs, no analytics trackers, no unnecessary permissions. Your calculations are stored locally and never leave your device. DESIGNED FOR EVERYONE • VoiceOver and TalkBack labels on every key • Light and dark themes with 8 color options and 6 button styles • Large touch targets and haptic feedback on every button • Full iPad support with Split View and hardware keyboards FREE TO START, PAY ONCE TO UNLOCK Two calculator panels and basic mode are free, forever. One purchase unlocks everything — scientific mode, programmer mode, full unit converter, extra panels, shared value tray, full history with search and export, themes, and more. No subscriptions. No recurring charges.

Screenshots

RPN4 screens
CalcBoard4 screens

Verdict

The call

The clearest difference is price: CalcBoard at Free against RPN's $4.99. CalcBoard also leads on update cadence (every 3 months vs every 7 months). RPN's advantage is in-app purchases (none vs 1). 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

CalcBoard is free to download; RPN costs $4.99 up front. CalcBoard sells 1 one-off in-app purchase. RPN asks for nothing beyond the download.

UpkeepUpdate frequency

RPN ships an update every 7 months, CalcBoard every 3 months. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard3 real differences · 6 level
RPN versus CalcBoard: the parameters behind the verdict, then further details
ParameterRPNCalcBoard
Price$4.99Free — better
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 7 monthsEvery 3 months — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad, Mac — betteriPhone, iPad
Requires iOS16.616.0 — better
Further details — not scored
Size1 MB50 MB
Age rating4+4+
DeveloperSteven DaviesColby Clark

In-app purchases

None

RPN

No in-app purchases

1 purchases

CalcBoard

One-time1
  • CalcBoard Premium$2.99

Questions

Is RPN free?
RPN costs $4.99, with no in-app purchases.
Is CalcBoard free?
CalcBoard is free to download, with in-app purchases available.
Do RPN or CalcBoard have ads?
Neither RPN nor CalcBoard shows ads.
Which is updated more often, RPN or CalcBoard?
RPN ships an update every 7 months, and CalcBoard every 3 months. Most recently, RPN was updated on November 3, 2026 and CalcBoard on October 31, 2026.

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