Comparison

Calculator 4U vs Sigma Notepad Calculator

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

Head to head
About

Calculator 4U

Features
Read full description

Experience the perfect blend of style and substance with our sleek, modern calculator. Designed for speed, accuracy, and ease of use, it handles everyday math as well as advanced calculations—making it ideal for students, professionals, and anyone who loves a beautiful, powerful tool. Key Features: • Modern Interface: Enjoy a visually appealing design with smooth gradients and rounded buttons for a stress-free user experience. • Advanced Math Tools: Perform complex operations (addition, subtraction, multiplication, division, and more) with complete precision. • History Tracking: Quickly revisit previous calculations. Swipe through, rewind, or fast-forward your history, so you never lose track of important results. • Fast Load & Haptic Feedback: Dive straight into calculations without delay. Optional sound effects make button presses feel satisfying. • Intuitive Controls: Toggle signs, use percentages, or clear the entire display with a tap. • Optimized for All Devices: Whether you’re on an iPhone or iPad, portrait or landscape, the layout adapts beautifully to your screen. Discover a calculator that not only looks good but also delivers every feature you need—right at your fingertips. Download now and see the difference!

About

Sigma Notepad Calculator

Features
Read full description

$610 left this month, before rent went out, and you never typed a sum. Sigma is a notepad that does the math while you write: every line shows its answer, and the total stays in view above the keyboard. Know what’s left before you spend it. Write "pay = $2400", then your bills, "rent: $1200" and "food: $380", and "left = pay - total" shows $820. Rent goes up? Change one number and everything below follows. Split the bill at the table. Dinner for four, tip included, comes to $51.75 each before anyone reaches for a card. Then send the whole sheet to the group chat as one image, every line and the total included. Know what the trip costs before you book. Flights in dollars, the hotel in euros, the train in Swiss francs: one total, all in, in your own currency. Rates stay live and keep working offline. Never add up the same list twice. Tick what’s paid and the total shows what’s still to pay. Give each part of a list a heading and each part gets its own total. And all the everyday math around it. How many days until an invoice is due. Whether a 220 cm sofa fits an 8 ft wall. What you really saved at the sale. What a week of freelance work comes to. Percentages, units, dates and currencies, written the way you’d say them, with square roots, hex and trigonometry when you need them. Every line answers as you type. No formulas, no grid, and one rule to learn: a colon counts, an equals sign doesn’t. Free: three sheets and the full calculator. No ads, no time limit. Sigma Pro keeps every month: unlimited sheets, iCloud sync, export to PDF, Markdown and plain text, and five more themes. Billed yearly, monthly, or once for life. New subscribers get a 7-day free trial on the yearly plan. Your sheets stay on your iPhone, and iCloud sync uses your own private iCloud database, never our servers. Works in English and French. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://getsigma.app/privacy

Screenshots

Calculator 4U4 screens
Sigma Notepad Calculator4 screens

Verdict

The call

The clearest difference is in-app purchases: Calculator 4U at none against Sigma Notepad Calculator's 3. On price, update cadence, ads 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. Sigma Notepad Calculator sells 3 in-app purchases, starting at $1.99 per month. Calculator 4U asks for nothing beyond the download.

UpkeepUpdate frequency

Calculator 4U ships an update every 3 weeks, Sigma Notepad Calculator fortnightly. The most recent releases landed on October 6, 2026 and October 25, 2026 respectively.

Scorecard1 real difference · 5 level
Calculator 4U versus Sigma Notepad Calculator: the parameters behind the verdict, then further details
ParameterCalculator 4USigma Notepad Calculator
PriceFreeFree
Update frequencyEvery 3 weeksFortnightly — better
AdsNoNo
In-app purchasesNo — betterYes
DevicesiPhoneiPhone
Requires iOS18.217.0 — better
Further details — not scored
Size2 MB16 MB
Age rating4+4+
DeveloperNaseer MohammedSoules Studio Ltd

In-app purchases

None

Calculator 4U

No in-app purchases

3 purchases

Sigma Notepad Calculator

Subscriptions2
  • Monthly$1.991 Month
  • Annual7 Days trial$14.991 Year
One-time1
  • Lifetime$29.99

Questions

Is Calculator 4U free?
Calculator 4U is free to download, with no in-app purchases.
Is Sigma Notepad Calculator free?
Sigma Notepad Calculator is free to download, with in-app purchases available.
Do Calculator 4U or Sigma Notepad Calculator have ads?
Neither Calculator 4U nor Sigma Notepad Calculator shows ads.
Which is updated more often, Calculator 4U or Sigma Notepad Calculator?
Calculator 4U ships an update every 3 weeks, and Sigma Notepad Calculator fortnightly. Most recently, Calculator 4U was updated on October 6, 2026 and Sigma Notepad Calculator on October 25, 2026.

Other comparisons