Comparison

OneCalc vs Simple Note

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

Head to head
About

OneCalc

This app offers a comprehensive suite of over 40 calculators and unit converters for various needs, including finance, health, construction, and everyday math. It features standard, scientific, and specialized calculators for tasks like loan amortization, currency conversion, and material estimation.

Highlights
  • Over 40 calculators and unit converters
  • Standard and scientific calculator functions
  • Financial calculators (interest, loan, currency)
  • Health calculators (BMI, calories, pace)
  • Construction material calculators
  • Date and time duration calculations
  • Business and shopping calculators
Features
Read full description

All-in-one Calculator is a free calculator app for iPhone and iPad featuring over 40+ calculators and unit converters categorized under finance, health, date & time, construction, shopping and everyday math. Simple yet powerful, the following features are built into this all-in-one calculator app:- STANDARD CALCULATOR • Includes percent key, negative sign, memory functions, brackets and history viewer. • Advanced mode includes functions for trigonometry, roots, exponents and logarithm found in scientific calculators. UNIT CONVERTER • Convert values between metric/ imperial units with conversion calculators for temperature, length, weight, area, volume and many more. FINANCIAL CALCULATORS • Interest calculators using simple and compound interest • Loan calculator with amortization schedule • Savings calculator to calculate future value and monthly savings amount • Currency converter HEALTH -Keep track of your body weight with these calculators:- • BMI calculator • Calories burnt calculator • Running Pace calculator EVERYDAY MATH • Percentage calculator • Fraction calculator • Rounding calculator • Area/ Volume calculator • Right-triangle calculator CONSTRUCTION -Estimate material requirements for small repair works/ DIY projects with these calculators:- • Brick calculator • Concrete calculator • Tiles calculator • Lumber volume calculator • Land area calculator DATE & TIME -Find duration between two date/ time values in months, weeks, days, hours, and minutes. • Date calculator (Also useful for age calculation) • Time calculator • Calculators to add/ subtract date and time BUSINESS -These calculators are useful when shopping and for those who run small business. • Profit margin calculator • Price markup calculator • Discount calculator • Tip and split calculator • Sales tax/ VAT calculator

About

Simple Note

Read full description

Simple Note is a clean, straightforward notepad for everyday notes, lists, reminders, and quick ideas. Ad-free. No tracking. Made in the USA. Open the app and start typing. Your current note is automatically saved as you work, so there is no separate Save button to remember. Features include: • Automatic saving while you type • Dot or numbered Auto Bullets • Adjustable text sizes • Your selected text size stays with the current note • A default text size for newly created notes • Easy sharing through the iOS Share Sheet • Simple Clear and Hide Keyboard controls • Light and Dark Mode support • No advertising • No user tracking • Privacy information and app settings available directly in the app Simple Note is designed to keep note-taking simple: one current note, quick access, and no unnecessary complexity. Important information should always be backed up or shared somewhere safe. See the app’s Important Notice and Privacy Information for additional details. Simple Note is developed in the USA.

Screenshots

OneCalc4 screens
Simple Note4 screens

Verdict

The call

The clearest difference is price: OneCalc at Free against Simple Note's $0.99. OneCalc also leads on device support (3 vs 1) and iOS requirement (15.6 vs 17.6). Simple Note's advantage is ads (none vs shown) and update cadence (every 8 days vs every 3 months). On in-app purchases 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

OneCalc is free to download; Simple Note costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

OneCalc ships an update every 3 months, Simple Note every 8 days. The most recent releases landed on November 2, 2026 and October 31, 2026 respectively.

Scorecard5 real differences · 5 level
OneCalc versus Simple Note: the parameters behind the verdict, then further details
ParameterOneCalcSimple Note
PriceFree — better$0.99
Rating4.6 (5.1K ratings) — better—
Positive reviews71.8% of reviews—
Number of ratings5.1K — better—
Update frequencyEvery 3 monthsEvery 8 days — better
AdsYesNo — better
In-app purchasesNoNo
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.6 — better17.6
Further details — not scored
Size6 MB2 MB
Age rating4+4+
Developertasser gyatiNicholas Milazzo

Bugs and requests

OneCalc

Reported bugs

3 issues
  • Crashes when using the 'More' section
  • Incorrect date duration calculations
  • Paid version still shows ads

Requested features

7 requests
  • Add more than 2 slots for conversions
  • Include a 'log' feature
  • Add a 'simplify fractions' unit
  • Improve the 'Date duration' calculator
  • Add a 'Business' mode with cost, sell, and margin keys
Show 2 more
  • Add a millimeters conversion option
  • Implement a 'clear' button to easily delete fields

Simple Note

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

OneCalc

No in-app purchases

None

Simple Note

No in-app purchases

Questions

Is OneCalc free?
OneCalc is free to download, with no in-app purchases.
Is Simple Note free?
Simple Note costs $0.99, with no in-app purchases.
Do OneCalc or Simple Note have ads?
OneCalc shows ads; Simple Note does not.
Which is updated more often, OneCalc or Simple Note?
OneCalc ships an update every 3 months, and Simple Note every 8 days. Most recently, OneCalc was updated on November 2, 2026 and Simple Note on October 31, 2026.

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