Comparison

A Complex Calc vs Scientific Calculator 991EX

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

Head to head
About

A Complex Calc

Perform complex calculations with a modern, user-friendly interface. Offers both basic and scientific modes, including support for complex numbers and advanced functions. This lightweight application provides a history of computations and is completely free with no advertisements.

Highlights
  • Complex number support
  • Basic and Scientific modes
  • History of operations
  • Trigonometric and hyperbolic functions
  • Random number generation
  • Lightweight app size
Features
Read full description

Work with complex numbers, scientific functions and unit conversions on your iPhone. A Complex Calc keeps your expression, result and next step together. EDIT WITHOUT STARTING OVER Place the cursor where you need a correction, reopen your latest submitted expression, or edit History entries that retain their original input. Paste supported expressions and review them before calculating. Undo and redo recent input changes during your current session. USE SCIENTIFIC TOOLS IN PORTRAIT Choose Basic or Scientific without rotating your phone. Keep trigonometric functions, logarithms, powers and constants close, with degree and radian controls. CONVERT UNITS ON THE SAME SCREEN Convert length, area, volume, mass, temperature, speed, energy, power, pressure, time, angles and electrical quantities. Swap compatible units, copy a converted value, and return to your calculator session. KEEP AND SHARE USEFUL WORK Mark History entries as favorites and filter them for quick access. Share a completed or saved calculation as text or a PNG image, with its recorded expression and result. SEE COMPLEX RESULTS CLEARLY Compare rectangular and polar forms, inspect the complex-plane diagram, and copy either representation. Clearer error guidance helps you correct an expression, while automatic scientific notation keeps small nonzero results visible. Requires iOS 18 or later.

About

Scientific Calculator 991EX

Features
Read full description

Scientific Calculator 991EX is a natural-display scientific calculator designed for students, engineers, and technical work. Calculate and Complex modes are free. Pro unlocks ten advanced modes: • Statistics • Distribution • Spreadsheet • Table • Equation/Func • Inequality • Base-N • Matrix • Vector • Ratio Calculate with fractions, roots, trigonometry, logarithms, calculus, constants, unit conversions, complex numbers, matrices, vectors, statistics, probability distributions, spreadsheets, function tables, equations, inequalities, and ratios. Choose natural or linear input, convert exact results to decimals, and use calculation history and replay without creating an account. Calculations, settings, history, and the locally generated calculator identifier are stored on your device. The app has no ads, tracking, analytics SDKs, accounts, or backend data collection. Pro is available as a monthly or yearly auto-renewing subscription, or as a one-time Lifetime purchase. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period; manage them in your Apple Account settings. Restore Purchases is available for devices using the same Apple Account. This independent app is not affiliated with or endorsed by any calculator manufacturer. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://matinformatics.org/privacy/scientific-calculator-fx-991ex

Screenshots

A Complex Calc4 screens
Scientific Calculator 991EX4 screens

Verdict

The call

The clearest difference is in-app purchases: A Complex Calc at none against Scientific Calculator 991EX's 3. A Complex Calc also leads on update cadence (every 4 weeks vs every 2 months). On price, 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

Both are free to download. Scientific Calculator 991EX sells 3 in-app purchases, starting at $0.99 per month. A Complex Calc asks for nothing beyond the download.

UpkeepUpdate frequency

A Complex Calc ships an update every 4 weeks, Scientific Calculator 991EX every 2 months. The most recent releases landed on October 29, 2026 and October 25, 2026 respectively.

Scorecard2 real differences · 8 level
A Complex Calc versus Scientific Calculator 991EX: the parameters behind the verdict, then further details
ParameterA Complex CalcScientific Calculator 991EX
PriceFreeFree
Rating4.7 (24 ratings) — better—
Positive reviews80.0% of reviews—
Number of ratings24 — better—
Update frequencyEvery 4 weeks — betterEvery 2 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhoneiPhone, iPad — better
Requires iOS18.017.0 — better
Further details — not scored
Size8 MB9 MB
Age rating4+4+
DeveloperAntonio RuffoloMurad Yaghi

In-app purchases

None

A Complex Calc

No in-app purchases

3 purchases

Scientific Calculator 991EX

Subscriptions2
  • Monthly Pro$0.991 Month
  • Yearly Pro$4.991 Year
One-time1
  • Lifetime Pro$14.99

Questions

Is A Complex Calc free?
A Complex Calc is free to download, with no in-app purchases.
Is Scientific Calculator 991EX free?
Scientific Calculator 991EX is free to download, with in-app purchases available.
Do A Complex Calc or Scientific Calculator 991EX have ads?
Neither A Complex Calc nor Scientific Calculator 991EX shows ads.
Which is updated more often, A Complex Calc or Scientific Calculator 991EX?
A Complex Calc ships an update every 4 weeks, and Scientific Calculator 991EX every 2 months. Most recently, A Complex Calc was updated on October 29, 2026 and Scientific Calculator 991EX on October 25, 2026.

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