Comparison

Calc Engine vs STRUCT Construction Calculator

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

Head to head
About

Calc Engine

A highly customizable calculator with advanced features like graphing, equation solving, and unit conversion. Design your own keyboards and functions to streamline your workflow across Apple devices.

Highlights
  • Customizable keyboard layouts
  • User-defined functions and constants
  • Live equation graphing
  • Equation solving
  • Extensive unit conversions
  • Programmer mode (hex, binary, octal)
  • Cross-device syncing
Features
Read full description

Calc Engine™ — The Calculator That Fits How You Work Whether you're splitting a dinner bill, plotting an equation, or working through bitwise logic, Calc Engine meets you where you are. It's a beautiful, fully customizable calculator that grows with you — and syncs seamlessly across iPhone, iPad, Mac, and Apple Watch. Make it look and feel like yours • Choose from rich color themes to match your style • Pick the fonts and key shapes that feel right in your hands • A calculator you actually enjoy opening Design keyboards your way • Build your own keyboard pages — drag any key from a curated library onto a 4×5, 5×5, or 6×5 grid • Mix digits, operators, scientific functions, your own constants — anything you reach for often, all in one place • Set a long-press alternate on any key so a single tile handles a primary and secondary action • Name each keyboard, pick its icon, and reorder it alongside the standard pages — your custom keyboards show up right where you'd expect them • Enable or disable any page (built-in or custom) per device Build your personal math library • Define your own functions with up to three parameters — name them whatever makes sense to you • Save the constants you use all the time and insert them with a single tap • Full calculation history, automatically saved — scroll back anytime Powerful math, always within reach • Trig (radians or degrees), logarithms, exponentials, roots, and more — there when you need them, out of the way when you don't • Live results as you type, so you always know where you're headed • Per-function rounding built in — perfect for money, measurements, or anything that needs a clean output Convert between hundreds of units in seconds • Tap a value, then any two units to see the conversion live — miles to km, lb to kg, °F to °C, gal to L, anything you need • 250+ built-in units across 40+ categories: length, mass, volume, temperature, time, speed, angle, energy, power, pressure, electrical, magnetic, optical, radioactivity, data, and more • Favorite the categories you actually use so they sit at the top — synced across your devices automatically • Build your own functions with conversions baked in — define a formula once and reuse it forever See your equations come to life in graphs • Plot equations like x = y² or sin(x) live as you type, right beside the keyboard • Tap any graph to expand into a full-screen view for closer inspection • A dedicated graphing keyboard with x, y, and = keeps everything in one place — no separate app, no separate mode Solve equations as you type • Type x² = 121 or sin(x) = 0.5 and Calc Engine finds every real answer • Tap the solved answers to reuse it in your next calculation, no separate "solve" mode Programmer mode without leaving the calculator • Type hex (0x), binary (0b), and octal (0o) literals — read and write the way you read code • A full bitwise toolkit: AND, OR, XOR, NOT, shifts, and rotates • Every result shown in HEX, DEC, OCT, and BIN simultaneously, with configurable word size (8/16/32/64) and signed/unsigned interpretation • Tap the binary row to expand into a byte-by-byte view with bit-position labels Private by design • Everything syncs through your personal iCloud — nothing stored on our servers • Fully localized and native on every Apple platform Unlock Calc Engine+ for the full experience — custom themes, fonts, key shapes, custom keyboards, user-defined functions, saved constants, unit conversions, live graphing, equation solving, programmer-mode hex/binary/bitwise, and more. Everything that makes Calc Engine truly yours. Teach it your formulas once. Customize it to feel like home. Use it forever.

About

STRUCT Construction Calculator

Features
Read full description

STRUCT — Construction Calculator Make your construction projects faster, easier, and more accurate. ProStruct is an all-in-one construction calculator designed for contractors, builders, engineers, architects, and DIY enthusiasts. Whether you’re planning a small home renovation or managing a large construction site, ProStruct helps you calculate materials, dimensions, and costs with confidence. All-in-One Construction Tools Simplify your daily work with a complete set of smart calculators: • Concrete volume calculations • Cement, sand, and material ratios • Brick and block quantity estimation • Wall and surface area calculations • Flooring and tiling measurements • Roofing calculations • Paint coverage estimation • And more essential tools for construction tasks Get instant results with clear formulas, helping you avoid costly mistakes and reduce material waste. Fast, Accurate & Reliable • Precise calculations in seconds • Built for real-world construction needs • Helps optimize materials and save costs Simple & Efficient Design Designed for speed and ease of use: • Clean, intuitive interface • Quick input and instant results • No clutter, no unnecessary features Just powerful tools when you need them most. Why Choose STRUCT? • All essential construction calculations in one app • Easy to use for professionals and beginners • Saves time, money, and effort on every project Download ProStruct today and take control of your construction calculations with confidence.

Screenshots

Calc Engine4 screens
STRUCT Construction Calculator3 screens

Verdict

The call

The clearest difference is in-app purchases: STRUCT Construction Calculator at none against Calc Engine's 1. STRUCT Construction Calculator also leads on iOS requirement (13.0 vs 18). Calc Engine's advantage is update cadence (daily vs every 4 months) and device support (4 vs 2). On price and ads 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. Calc Engine sells 1 one-off in-app purchase. STRUCT Construction Calculator asks for nothing beyond the download.

UpkeepUpdate frequency

Calc Engine ships an update daily, STRUCT Construction Calculator every 4 months. The most recent releases landed on August 31, 2026 and September 9, 2026 respectively.

Scorecard4 real differences · 5 level
Calc Engine versus STRUCT Construction Calculator: the parameters behind the verdict, then further details
ParameterCalc EngineSTRUCT Construction Calculator
PriceFreeFree
Rating5.0 (4 ratings) — better—
Number of ratings4 — better—
Update frequencyDaily — betterEvery 4 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree—
DevicesiPhone, iPad, Mac, Apple Watch — betteriPhone, iPod
Requires iOS1813.0 — better
Further details — not scored
Size17 MB16 MB
Age rating4+4+
DeveloperVersaEdge Software, LLCMOBILEXAPPS MB

In-app purchases

1 purchases

Calc Engine

One-time1
  • Calc Engine+$9.99
None

STRUCT Construction Calculator

No in-app purchases

Questions

Is Calc Engine free?
Calc Engine is free to download, with in-app purchases available.
Is STRUCT Construction Calculator free?
STRUCT Construction Calculator is free to download, with no in-app purchases.
Do Calc Engine or STRUCT Construction Calculator have ads?
Neither Calc Engine nor STRUCT Construction Calculator shows ads.
Which is updated more often, Calc Engine or STRUCT Construction Calculator?
Calc Engine ships an update daily, and STRUCT Construction Calculator every 4 months. Most recently, Calc Engine was updated on August 31, 2026 and STRUCT Construction Calculator on September 9, 2026.

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