# Kaodoku

> Symbol-based Sudoku variation with partially revealed elements. (iPhone/iPad app by Michel Colman.)

- Source: https://appshunter.io/ios/app/kaodoku/id923859724 (this page in markdown: same URL + `.md`)
- Developer: [Michel Colman](https://appshunter.io/developer/305429704)
- Category: Games, Entertainment, Puzzle
- Price: Free with in-app purchases
- Rating: 5.00/5 from 1 App Store ratings · 4 written reviews indexed
- Age rating: 4+
- Requires: iOS 9.0 · 4 MB
- Languages: American English
- Released: 2015-12-13
- Data updated: 2026-08-20
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/kaodoku/id923859724/reviews.md

## What is Kaodoku?

Kaodokus are a new variation of sudoku with symbols that are only partially given. Originally invented for Belgian Mensa magazine Commensal, kaodokus offer a lot more variety than ordinary sudokus. Instead of numbers, the cells contain smiley faces which can have three possible shapes and three possible mouths. Each of the nine unique combinations has to appear exactly once in each column, row or other marked area just like in a normal sudoku. The big novelty is that in some cells only the mouth or shape is given, leaving the missing part for you to find. You can even ask for grids that initially don't include a single full symbol! This makes the puzzle experience a lot richer, requiring complex strategies combining bits and pieces of information in original ways.

Features:
- Normal grids completely free, with as many randomly generated puzzles as you like in many different levels of difficulty.
- With a single in-app purchase, you can unlock more complex puzzles with extra diagonals, gray squares and chaotic grids which require even deeper thinking combining all those intersecting regions.
- Sophisticated hint system which actually suggests possible ways forward using step by step logic. Especially in the beginning this is very helpful since even the easiest kaodoku grids can be daunting for those not used to them.
- Activate pencil notes in the settings so you can zoom in and freely draw whatever doodles you like, just like you would on paper.
- Alternatively, you can also use standard candidate marks to keep track of the possible symbols in each cell. In very difficult puzzles, the hints function will take these candidate marks into account if they are the only way of making progress.
- Share puzzles with others, export them in pdf or png format, or print them on paper to solve them the old-fashioned way. Feel free to publish puzzles in magazines or on websites, as long as you don't remove the kaodoku web address.

## Key features

- Symbol-based Sudoku puzzles
- Partially revealed symbols
- Multiple difficulty levels
- Sophisticated hint system
- Pencil notes and candidate marks
- Export and print puzzles

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Full version of Kaodoku | $0.99 | one-time |


## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/kaodoku/id923859724/reviews.md

### 5/5 — Excellent jeu

*2025-01-15, version 1.1.10*

Comme le sudoku, mais en mieux! Super jeu, super interface, pas de pubs, il vaut vraiment le détour!!

### 5/5 — Super

*2016-12-20, version 1.1.1*

Super leuk concept. Het is echt een aanrader. En het is natuurlijk ook heel mooi uitgewerkt. Proficiat Michel!

### 5/5 — Devilishly Difficult

*2016-01-02*

We spent much of Christmas trying to solve these devilishly difficult puzzles......Adds a completely different dimension using symbols....All you could hear was, references to sad triangle, happy squares and neutral circles.....As we all did our thinking out loud...!!

### 5/5 — Sudoku+

*2015-12-14, version 1.0*

Frankly, one of the only things I look forward to every month when the new Commensal (Mensa Belgium monthly) comes out: the smileydoku's...
Won't have to wait no longer, can play as many as I want now... :-)  (rebaptized as kaodoku)
In a sense it is easier than your regular sudoku, in that you can fix partial answers, but this results in an entirely new depth and strategy to sudoku's that makes the game all the more interesting...

## Frequently asked questions about Kaodoku

### What makes Kaodoku different from regular Sudoku?

Kaodoku uses symbols with three shapes and three mouths instead of numbers. The key difference is that some cells only show part of a symbol, requiring you to deduce the missing element.

### Can I play Kaodoku offline?

The description does not specify offline play capabilities. However, typical puzzle games of this nature often function without an internet connection.

### Does Kaodoku have ads?

No, Kaodoku does not contain advertisements. The app is free to download and play, with optional in-app purchases for advanced puzzles.

### What are the in-app purchases in Kaodoku?

A single in-app purchase unlocks more complex puzzles featuring extra diagonals, gray squares, and chaotic grids that demand deeper strategic thinking.

### How does the hint system in Kaodoku work?

The sophisticated hint system provides step-by-step logic suggestions to guide players, which is particularly helpful for beginners or on more challenging grids.

### What devices is Kaodoku available on?

Kaodoku is available on iPhone, iPad, and iPod devices, as indicated by the supported devices list.

### How often is Kaodoku updated?

The latest version is 1.1.11, last updated on March 27, 2026. This suggests a relatively infrequent but consistent update schedule.

### What is the age rating for Kaodoku?

Kaodoku has an age rating of 4+, making it suitable for a wide range of players, including younger audiences interested in logic puzzles.

## Version history (last 5 releases)

### 1.1.11 — 2026-03-27

Fixed a rare crashing bug in the hints function

### 1.1.10 — 2024-04-30

Minor cosmetic changes

### 1.1.9 — 2022-11-13

Fixed a very minor and rare bug where sometimes pen marks would be a different color instead of the normal blue.

### 1.1.8 — 2021-10-17

Fixed a minor bug where puzzles with both full and half given symbols would on average tend to contain more mouths than shapes. Both are now equally likely.

### 1.1.7 — 2018-10-03

- Added a "Beginner" difficulty setting since even "Very Easy" could still be a bit daunting for people who see a kaodoku for the first time. Beginner mode only works with full or mixed symbols, not half symbols.
- Improved the difficulty rating algorithm somewhat

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## More apps by Michel Colman

- [Moving Puzzle](https://appshunter.io/ios/app/moving-puzzle/id311474754)
- [Colibricks](https://appshunter.io/ios/app/colibricks/id361312496)

All apps by Michel Colman: https://appshunter.io/developer/305429704

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-20.*