# SumSudoku: Killer Sudoku — Crossovers with Kakuro flavor

> Logic puzzle game combining Sudoku and Kakuro with sum-based area clues. (iPhone/iPad app by Conceptis Ltd..)

- Source: https://appshunter.io/ios/app/sumsudoku-killer-sudoku/id1259275580 (this page in markdown: same URL + `.md`)
- Developer: [Conceptis Ltd.](https://appshunter.io/developer/479420055)
- Category: Games, Entertainment, Board, Puzzle
- Price: Free with in-app purchases
- Rating: 4.80/5 from 801 App Store ratings · 236 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.6 · 11 MB
- Languages: American English, Korean, Chinese (Simplified, China), Japanese
- Released: 2017-11-23
- Data updated: 2026-08-27
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/sumsudoku-killer-sudoku/id1259275580/reviews.md

## What is SumSudoku?

Play a crossover variation of Sudoku and Kakuro! SumSudoku, also known as Killer Sudoku, are addictive logic puzzles best described as a cross between Sudoku and Kakuro. Using pure logic and simple add/subtract calculations, these fascinating puzzles offer endless fun and intellectual entertainment to puzzle fans of all skills and ages.

Each puzzle consists of a 9x9 Sudoku grid containing areas surrounded by dark borders. The object is to fill all empty squares so that the numbers 1 to 9 appear exactly once in each row, column and 3x3 box, and the sum of the numbers in each area is equal to the clue in the area's top-left corner. In addition, no number may be used in the same area more than once.

The game includes helpful features such as showing possible sum number combinations in an area and pencilmarks to make temporary placement of numbers in the grid. To help see the puzzle progress, graphic previews in the puzzle list show the progress of all puzzles in a volume as they are being solved. A Gallery view option provides these previews in a larger format.

For more fun, SumSudoku contains no ads and includes a Weekly Bonus section providing an extra free puzzle each week.

PUZZLE FEATURES

• 120 free SumSudoku puzzle samples
• Extra bonus puzzle published free each week
• Multiple difficulty levels from easy to very hard
• Puzzle library continuously updates with new content
• Manually selected, top quality puzzles
• Unique solution for each puzzle
• Hours of intellectual challenge and fun
• Sharpens logic and improves cognitive skills

GAMING FEATURES

• No ads
• Unlimited check puzzle
• Unlimited hints
• Show conflicts during gameplay
• Unlimited Undo and Redo
• Show possible sum combinations option
• Pencilmarks feature for solving hard puzzles
• Autofill pencilmarks mode
• Highlight Excluded Squares option
• Lock number on keypad option
• Concurrently playing and saving multiple puzzles
• Puzzle filtering, sorting and archiving options
• Dark Mode support
• Graphic previews showing puzzles progress as they are being solved
• Portrait and landscape screen support (iPad only)
• Track puzzle solving times
• Backup & restore puzzle progress to iCloud

ABOUT

Conceptis SumSudoku have also become popular under other names such as Killer Sudoku, Sumdoku and Sumoku.  All puzzles in this app are produced by Conceptis Ltd. - the leading supplier of logic puzzles to printed and electronic gaming media all over the world. On average, more than 20 million Conceptis puzzles are solved each day in newspapers, magazines, books and online as well as on smartphones and tablets across the world.

Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://www.conceptispuzzles.com/index.aspx?uri=info/doc/220

## Key features

- Killer Sudoku puzzles
- Kakuro-style sum clues
- Logic and calculation based
- Hints and pencilmarks
- Progress previews
- Weekly bonus puzzles
- Multiple difficulty levels

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Easy 1 | $0.99 | one-time |
| Medium 1 | $1.99 | one-time |
| Hard 1 | $1.99 | one-time |
| Killer 1 | $1.99 | one-time |
| Medium 2 | $1.99 | one-time |
| Hard 2 | $1.99 | one-time |
| Killer 2 | $1.99 | one-time |
| Medium 3 | $1.99 | one-time |
| Hard 3 | $1.99 | one-time |
| Killer 3 | $1.99 | one-time |
| Hard 4 | $1.99 | one-time |
| Killer 68 | $1.99 | one-time |
| Hard 5 | $1.99 | one-time |
| Killer 101 | $1.99 | one-time |
| Medium 76 | $1.99 | one-time |
| Hard 80 | $1.99 | one-time |
| Killer 79 | $1.99 | one-time |
| Hard 77 | $1.99 | one-time |
| Hard 76 | $1.99 | one-time |
| Killer 7 | $1.99 | one-time |


## What do users think of SumSudoku?

Overall sentiment: positive

**Pros**

- 👍 Challenging and fun puzzles
- 🚀 Intuitive interface and controls
- 🔒 No ads or in-app purchases
- 💡 Variety of difficulty levels
- 👍 Helps keep the mind sharp

**Cons**

- 🐛 Occasional crashes or freezes
- 💡 Difficulty levels not always consistent
- 💡 Lack of customization options (colors, etc.)

**Commonly reported bugs**

- Some puzzles have incorrect sums or repeated numbers
- Autofill feature doesn't always work as expected

**Most requested features**

- Add ability to select difficulty level for weekly bonus puzzles
- Implement a 'dark mode' option
- Allow users to cross out/eliminate number possibilities
- Add a 'one-tap' feature to fill in all 9 numbers in a cell

## Recent user reviews (10 of 236)

All indexed reviews: https://appshunter.io/ios/app/sumsudoku-killer-sudoku/id1259275580/reviews.md

### 5/5 — 最高

*2026-07-06*

面白すぎて時間が溶けます！

### 5/5 — おもしろい

*2026-06-16*

やりがいがあります。広告が無いのがいい。

### 5/5 — 夢中になっています

*2026-06-09*

毎日楽しくプレイしています。広告が出なくて軽いし、機能もとても使いやすいです。上級のパズルが解けた時は至上の快感！元々基本無料なのに、ウィークリーボーナスでパズルが配信されるのもお得すぎていいのかな？と思ってしまうくらいです。これからもたくさん楽しませていただきます！

### 5/5 — アプデありがとうございます

*2026-04-20*

毎日のようにあそんでいます。数あるパズルアプリの中でこちらの会社のアプリはどれも操作性の良さ、無料で遊べる数、複数の難易度、良価格帯、無広告…と群を抜いています。

**Developer response:** レビューいただきありがとうございます。最近のアップデートでzoom機能等を盛り込み、フリックで数字のヒントが見れなくなり申し訳ございません。只今諸々修正作業をしております。数字のコンビネーションはキーパッドのΣで表示されますのでお試しください。

### 4/5 — 色々と元に戻った👍

*2026-04-13*

対応ありがとうございます😊

**Developer response:** レビューいただきありがとうございます。最近のアップデートでzoom機能等を盛り込んだため、Σでしか数字のヒントが見れなくなり申し訳ございません。只今諸々修正作業をしております。
修正作業が終わりましたので、スワイプで数字のコンビネーションを表示いただけます。お試しいただけましたら幸いです。

### 5/5 — The swipe issue has been fixed!

*2026-04-12, version 3.4*

Thanks for adding back the swipe feature. Now this is the best SumSudoku app in the App Store.

### 5/5 — とても楽しんでいます

*2026-04-10*

こちらは中級が丁度よくプレイしています。ウィークリーボーナスも有り難いです。それからスワイプ表示の不具合修正ありがとうございました。

### 3/5 — アプデがイマイチ

*2026-04-05*

長年楽しんでるアプリ。無料でも買っても楽しめる。しかし、アプデでせっかくの操作性と視認性の良さが失われました。数字ボタンの色が紛らわしく、拡大も必要なかった。他のより群を抜いて良かったのに。アプデするんじゃなかった。

**Developer response:** 申し訳ありませんでした。その後、改善版をアップしました。

### 2/5 — Assistant Feature not always helpful

*2026-04-03, version 3.3*

I’ve been using this app for some time, and have always found it very good. The new Assistant feature is a useful addition if you are really stuck, but it relies on you using the Auto-fill feature. If I have carefully filled in the possibilities in small digits, then get stuck and turn on Auto-fill, it will sometimes add additional “possibilities”, that I have already deduced are “impossibilities”. e.g. If I know that the number 1 can only be in row 3 within a certain cell, Auto-fill will add the number 1 to row 3 in other cells on that level, if there are no other constraints … do I then need to remove them again manually! (This bug also exists in the Auto-fill feature in Multi-Sudoku)

Updated 28 March 2023.
Thanks for the feedback on my previous comments!
My next comment is that I wish there was a “help” feature for the different types of hint the Assistant produces. Most I understand … but e.g. for “Sum Area Combinations” I wish it could step me through how it arrived at the conclusion, so I can learn for myself to apply that next time.

03 April 2026
The latest update seems to have lost the ability to highlight an area and see what the number combinations are for that area.  This makes the game almost unplayable.

### 1/5 — Swipe for sum

*2026-04-01, version 3.3*

Bring back the swipe for sum feature.

## Frequently asked questions about SumSudoku

### What is SumSudoku?

SumSudoku is a logic puzzle game that blends elements of Sudoku and Kakuro. Players fill a 9x9 grid with numbers 1-9, ensuring each number appears once per row, column, and 3x3 box. Additionally, the sum of numbers within designated areas must match the clue provided in the top-left corner of each area.

### What are the key features of SumSudoku?

The app offers 120 free puzzles, a weekly bonus puzzle, multiple difficulty levels, and a continuously updating puzzle library. Helpful gaming features include unlimited hints, undo/redo, conflict highlighting, pencilmarks, and graphic previews of puzzle progress.

### Is SumSudoku free to play?

The app is free to download and play, offering a significant number of free puzzles and a weekly bonus puzzle. While the core game is free, it does have in-app purchases, likely for additional puzzle packs or content.

### What platforms is SumSudoku available on?

Based on the provided information, the app supports Portrait and landscape screen modes on iPad. It is designed for mobile devices, suggesting availability on iOS platforms.

### What are the benefits of playing SumSudoku?

Playing SumSudoku provides hours of intellectual challenge and fun. It sharpens logic skills, improves cognitive abilities, and offers a satisfying mental workout through its addictive logic puzzles.

## Version history (last 5 releases)

### 3.4 — 2026-04-09

This version fixes the issue of showing sum-combinations by swiping finger on a block.

### 3.3 — 2026-03-21

This version improves performance and stability.

### 3.2 — 2025-10-24

This version improves performance and stability.

### 3.1 — 2025-08-06

This version improves performance and stability.

### 3.0 — 2025-03-19

This version improves performance and stability.

## Apps similar to SumSudoku

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Killer Sudoku by Logic Wiz](https://appshunter.io/ios/app/killer-sudoku-by-logic-wiz/id1641151077) | 4.9 (188) | Free | Games |
| [Sudoku World - Brainstorming!!](https://appshunter.io/ios/app/sudoku-world-brainstorming/id463419280) | 4.7 (1,493) | Free | Games |
| [Sudoku Mega Bundle](https://appshunter.io/ios/app/sudoku-mega-bundle/id970674839) | 4.8 (2,874) | Free | Games |
| [Super Sudoku - Brainstorming!!](https://appshunter.io/ios/app/super-sudoku-brainstorming/id1176140605) | 4.7 (1,454) | Free | Games |
| [Samurai Sudoku](https://appshunter.io/ios/app/samurai-sudoku/id594421598) | 4.6 (374) | Free | Games |
| [Killer Sudoku - number game](https://appshunter.io/ios/app/killer-sudoku-number-game/id1576305047) | 4.8 (182) | Free | Games |

## More apps by Conceptis Ltd.

- [Fill-a-Pix: Minesweeper Puzzle](https://appshunter.io/ios/app/fill-a-pix-minesweeper-puzzle/id479420052)
- [Pic-a-Pix: Nonogram Color](https://appshunter.io/ios/app/pic-a-pix-nonogram-color/id503132420)
- [Link-a-Pix: Nonogram Links](https://appshunter.io/ios/app/link-a-pix-nonogram-links/id517602670)
- [Sudoku: Classic & Variations](https://appshunter.io/ios/app/sudoku-classic-and-variations/id537201666)
- [Hashi: Bridges](https://appshunter.io/ios/app/hashi-bridges/id567583852)
- [Nurikabe: Islands & Walls](https://appshunter.io/ios/app/nurikabe-islands-and-walls/id581912445)

All apps by Conceptis Ltd.: https://appshunter.io/developer/479420055

## Related topics

[sumoku](https://appshunter.io/ios/topics/sumoku)

---

*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 2026-08-27.*