Comparison

Smart Instant Calculator vs Calculator Plug

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

Head to head
About

Smart Instant Calculator

Features
Read full description

◇Why Smart Calculator?◇ ・Real-time results: No “=” required—answers appear as you type. ・Widget-first: Do the math right on the Home Screen, then hand off values to the app. ・Keep & Drop: Ditch confusing M+/M−. Save a value with Keep, remove it with Drop—simple and intuitive. ・Only the essentials: All the everyday functions you actually use. ・Designed for comfort: Clean UI and eye-friendly colors for long sessions. ・Completely free: Every feature, no paywall. ◇Recommended For◇ ・You want a clean, straightforward calculator ・The default calculator feels limited ・You prefer instant results and minimal taps ・Opening an app for every quick calc is a hassle

About

Calculator Plug

Access over 450 specialized calculators for construction, finance, health, trades, and more. This app offers a clean, offline-capable interface for quick, accurate calculations without intrusive ads.

Highlights
  • 450+ searchable calculators
  • Offline functionality
  • Clean dark interface
  • Construction calculators
  • Finance calculators
  • Health and fitness calculators
  • Trades calculators
Features
Read full description

Calculator Plug puts 450+ real-world calculators in one fast, clean app - built for people who need a real answer, not a search engine full of pop-ups. CATEGORIES - Construction and home: concrete, drywall, flooring, roofing, framing, square footage - Finance and money: mortgage, loan, refinance, compound interest, ROI, retirement - Health and fitness: BMI, calories, macros, body fat, heart rate, pace - Math and science: algebra, geometry, statistics, chemistry, physics - Trades: electrical, plumbing, HVAC, welding, structural engineering - Trading and investing: position size, pip value, cost basis, capital gains - Conversions, automotive, business, date and time, and more - Field pack: local weather, tides, sunrise/sunset and moon times FEATURES - 450+ calculators, searchable in a tap - Works offline (except live weather and tides) - Pro unlocks every calculator; Pro+ adds the professional suite - Clean dark interface, no clutter Free to use with a core set. Pro and Pro+ unlock the full library. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Smart Instant Calculator4 screens
Calculator Plug4 screens

Verdict

The call

The clearest difference is in-app purchases: Smart Instant Calculator at none against Calculator Plug's 4. Calculator Plug's advantage is ads (none vs shown) and update cadence (every 4 days vs every 2 months). On price 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

Both are free to download. Calculator Plug sells 4 in-app purchases, starting at $5.99 per month. Smart Instant Calculator asks for nothing beyond the download.

UpkeepUpdate frequency

Smart Instant Calculator ships an update every 2 months, Calculator Plug every 4 days. The most recent releases landed on October 25, 2026 and October 14, 2026 respectively.

Scorecard4 real differences · 5 level
Smart Instant Calculator versus Calculator Plug: the parameters behind the verdict, then further details
ParameterSmart Instant CalculatorCalculator Plug
PriceFreeFree
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 2 monthsEvery 4 days — better
AdsYesNo — better
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS18.015.1 — better
Further details — not scored
Size8 MB34 MB
Age rating4+4+
DeveloperIchi HosotsujiMark Gabrielli

In-app purchases

None

Smart Instant Calculator

No in-app purchases

4 purchases

Calculator Plug

Subscriptions2
  • Pro Monthly$5.991 Month
  • Pro+ Monthly$9.991 Month
One-time2
  • Pro Lifetime$29.99
  • Pro+ Lifetime$44.99

Questions

Is Smart Instant Calculator free?
Smart Instant Calculator is free to download, with no in-app purchases.
Is Calculator Plug free?
Calculator Plug is free to download, with in-app purchases available.
Do Smart Instant Calculator or Calculator Plug have ads?
Smart Instant Calculator shows ads; Calculator Plug does not.
Which is updated more often, Smart Instant Calculator or Calculator Plug?
Smart Instant Calculator ships an update every 2 months, and Calculator Plug every 4 days. Most recently, Smart Instant Calculator was updated on October 25, 2026 and Calculator Plug on October 14, 2026.

Other comparisons