Comparison

Drastic Calc vs CalcBoard

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

Head to head
About

Drastic Calc

Features
Read full description

Drastic Calc brings the excitement of retro games to your daily calculations! Why just calculate when you can play? Experience the satisfying "click" and "bang" with every tap. 【Features】 • Authentic Retro Design: Classic 80s calculator aesthetic with solar panel styling. • Dynamic Sound Themes: Choose from Gunshot, Explosion, 8-bit Game sounds, and more. • Satisfying Feedback: Every button press feels like a game action. • Simple & Useful: Fully functional standard calculator for your daily needs. 【Sound Themes Include】 - Gunshot - Explosion - Retro Game (8-bit) - And more! Make your calculations drastic and fun!

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

Drastic Calc3 screens
CalcBoard4 screens

Verdict

The call

The clearest difference is in-app purchases: Drastic Calc at none against CalcBoard's 1. Drastic Calc also leads on update cadence (weekly vs every 3 months). CalcBoard's advantage is ads (none vs shown). On price, 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

Both are free to download. CalcBoard sells 1 one-off in-app purchase. Drastic Calc asks for nothing beyond the download.

UpkeepUpdate frequency

Drastic Calc ships an update weekly, CalcBoard every 3 months. Both last shipped on October 28, 2026.

Scorecard3 real differences · 6 level
Drastic Calc versus CalcBoard: the parameters behind the verdict, then further details
ParameterDrastic CalcCalcBoard
PriceFreeFree
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyWeekly — betterEvery 3 months
AdsYesNo — better
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.016.0 — better
Further details — not scored
Size15 MB50 MB
Age rating9+4+
DeveloperTatsuro FuruyaColby Clark

In-app purchases

None

Drastic Calc

No in-app purchases

1 purchases

CalcBoard

One-time1
  • CalcBoard Premium$2.99

Questions

Is Drastic Calc free?
Drastic Calc is free to download, with no in-app purchases.
Is CalcBoard free?
CalcBoard is free to download, with in-app purchases available.
Do Drastic Calc or CalcBoard have ads?
Drastic Calc shows ads; CalcBoard does not.
Which is updated more often, Drastic Calc or CalcBoard?
Drastic Calc ships an update weekly, and CalcBoard every 3 months. Most recently, Drastic Calc was updated on October 28, 2026 and CalcBoard on October 28, 2026.

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