Comparison

KumamonCalc vs O'der stack

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

Head to head
About

KumamonCalc

A straightforward calculator featuring the popular Kumamon character. It supports basic arithmetic, percentage calculations, and memory functions. Users can customize themes and toggle sound effects.

Highlights
  • Basic arithmetic operations
  • Percentage calculation
  • Memory function
  • Customizable themes
  • Sound ON/OFF option
  • 12-digit input support
Features
Read full description

Simple calculator famous character in Japan " Kumamon " appeared ! Corresponds to the percentage calculation arithmetic , % , it is equipped with a memory function . It is a computer that does not correspond to the function operation . It is a calculator of the calculation Kumamon addition, subtraction , multiplication , division , percentages , can be . ※ Kumamon calculator is free , but you can hide the ads by purchasing the extension plug-in . [ Main function ] - Input the number of digits to 12 digits - Support for iPad - Can change the theme Settings Sound : ON / OFF Theme : black / white / red / yellow / blue / green © 2010 kumamoto pref. Kumamon #13492

About

O'der stack

Features
Read full description

O'der stack is a scientific calculator that is precise for up to 38 digits and is highly flexible. It can be used for various purposes, from learning to professional use, and has many functions that are convenient when mastered. The formulas described can be saved together with the results of the calculations and easily shared among members. Also, labels and memos can be set for formulas as well as each item that makes up the formulas. For example, by adding the label "radius" to "50" in 2 x 50 x π, it is possible to make the meaning of the formula even clearer. It is also perfect for entering explanations of formulas as memos and using them as tools to assist in learning. O'der stack offers two plans, the Pro plan which offers unlimited use of all functions, as well as the Free plan which makes it usable as an easy-to-use scientific calculator. —Functions— 1. A powerful editing function that allows partial overwriting of values without erasing the formula 2. Label and memo functions to support the understanding of formulas 3. A clipboard function that allows formulas to be pasted in notebooks, etc. 4. Setting the precision of calculations from 0 digits to 38 digits 5. Setting units (degrees/radians) for trigonometric functions 6. Setting the format of displaying results of calculations (normal notation, scientific notation, and percentage notation) 7. Basic functions (exponentiation and nth root) 8. Undo function —Pro plan— Please download O'der stack and try out the Pro plan for free for seven days. In addition to all the functions in the Free plan, the Pro plan allows for the activation of even more convenient functions. 1. Functions to save and load formulas and calculation histories 2. Function to share formulas and calculation histories 3. A sub-formula function that allows for the breakdown into several formulas and simple entry 4. 18 types of versatile and widely-used functions 5. 652 highly precise numerical and physical constants and observed values 6. Setting the format of displaying results of calculations (binary, octal, hexadecimal)        - Each item can be selected from 8bit, 16bit, 24bit, 32bit, 64bit and 128bit.        - Supports negative values and decimal points.        - Negative values are displayed in complement. After the free trial has ended, if you would like to continue to use the Pro plan, a purchase of a non-autorenew-subscriptionis required. For a subscription, you can choose either a monthly purchase or yearly purchase, and the yearly purchase allows you to enjoy a discount worth two months of monthly purchases. Payment will be charged to your Apple ID account at the confirmation of purchase. If you purchase a plan during the effective period, it will be extended by the number of days of the purchased plan from the end date. The plan is effective on all devices linked to the purchased Apple ID account. Privacy policy https://ictfractal.github.io/official/PrivacyPolicy.html Terms of service https://ictfractal.github.io/official/AppTerms.pdf Disclaimer ICT Fractal Inc. does not guarantee the accuracy, credibility, and compatibility of the results of calculations and information provided through this app. Furthermore, it does not bear the responsibility for direct or indirect damages that might occur through this app.

Screenshots

KumamonCalc1 screens
O'der stack4 screens

Verdict

The call

The clearest difference is ads: O'der stack at none against KumamonCalc's shown. KumamonCalc's advantage is iOS requirement (13.0 vs 15.6). On price, update cadence, in-app purchases 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. KumamonCalc sells 1 one-off in-app purchase and O'der stack sells 3 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on November 1, 2026 and November 6, 2026 respectively.

Scorecard2 real differences · 8 level
KumamonCalc versus O'der stack: the parameters behind the verdict, then further details
ParameterKumamonCalcO'der stack
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews80.0% of reviews—
Number of ratings2 — better—
Update frequencyEvery 3 monthsEvery 3 months
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.0 — better15.6
Further details — not scored
Size50 MB59 MB
Age rating4+4+
Developerwoodsmall inc.ICT Fractal Inc.

In-app purchases

1 purchases

KumamonCalc

One-time1
  • Advertising hide$4.99
3 purchases

O'der stack

One-time3
  • Free trial for 7 days.Free
  • Activate for 1 month.$0.99
  • Activate for year.$9.99

Questions

Is KumamonCalc free?
KumamonCalc is free to download, with in-app purchases available.
Is O'der stack free?
O'der stack is free to download, with in-app purchases available.
Do KumamonCalc or O'der stack have ads?
KumamonCalc shows ads; O'der stack does not.
Which is updated more often, KumamonCalc or O'der stack?
KumamonCalc ships an update every 3 months, and O'der stack every 3 months. Most recently, KumamonCalc was updated on November 1, 2026 and O'der stack on November 6, 2026.

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