# Nine: Sudoku That Explains — Names the technique every time

> Names the technique every time (iPhone/iPad app by Balthazar Van de Velde.)

- Source: https://appshunter.io/ios/app/nine-sudoku-that-explains/id6813644818 (this page in markdown: same URL + `.md`)
- Developer: [Balthazar Van de Velde](https://appshunter.io/developer/6809029359)
- Category: Games, Board, Puzzle
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 15.0 · 18 MB
- Languages: American English
- Released: 2026-09-22
- Data updated: 2026-10-11

## What is Nine?

Every sudoku app has a hint button. You press it, a digit appears, and you have learned nothing. Next time you are stuck in the same place.

Nine does it differently. You get one explanation per puzzle, and it fills in nothing. It names the technique, highlights the row, column or box where the proof is, and spells out the reasoning:

"ONLY PLACE. In the bottom right box the 7 can only go here. The 7s in row 8 and column 9 rule out the other cells."

"POINTING PAIR. In the bottom right box the 5 can only go in row 8. So the 5 is out everywhere else in row 8. That leaves column 2 with only one place for the 5: here."

Then you place it yourself. You learn something instead of being handed the answer.

THE PUZZLES
Four difficulty levels, 30 levels each. Difficulty does not come from the number of given digits, but from the techniques needed to solve: from lone digits to triples and X-wing. Every puzzle is verified to have exactly one solution. Guessing is never required.

THE EIGHT TECHNIQUES
Only option, only place, pointing pair, box claimed, naked pair, hidden pair, naked triple and X-wing. Together they solve every puzzle in Nine. Each one has its own page with an example board where you see it happen, and when an explanation uses one you tap its name to read what it is.

THE RULES
Three mistakes and the puzzle restarts. One explanation. Three stars if you finish without either.

A NEW ONE EVERY DAY
Everyone gets the same daily puzzle, with Sunday as the hardest, just like the newspaper. Your streak sits on the home screen.

ALSO
• Notes, undo, automatic saving
• Your own times and statistics per difficulty
• Light and dark mode
• Dutch, English, French, German, Turkish, Spanish and Portuguese

TRY IT FREE
Play everything free for 7 days. After that, unlock Nine with a one-time purchase, no subscription. Nothing is ever charged automatically.

WHAT IS NOT IN IT
No ads. No account. No subscription. No internet needed to play. The app collects nothing and sends nothing: your progress lives on your device and nowhere else.

Made in Belgium by Made by Balthazar.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| 7-Day Trial | Free | one-time |
| Nine Lifetime | $3.99 | one-time |


## Is Nine safe?

Not enough ratings yet to assess Nine.

## Is Nine legit?

Nine: Sudoku That Explains has limited verification signals. The AppsHunter Legitimacy Score for Nine is 58 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 4 releases)

### 1.3 — 2026-09-29

New: Learn to play. A short lesson on a real board with the real buttons. It shows the rule, how to place a digit, what a mistake does, the notes, and the explanation Nine gives when you are stuck. Seven steps, about two minutes, and you cannot lose.

You find it on the home screen, and it stays under the (i) so you can do it whenever you like.

The explanation now names the technique it uses: pointing pair, hidden pair, naked triple, X-wing. Tap the name and you read what that technique is, with an example board where you see it happen. All eight are together under the (i).

### 1.2 — 2026-09-25

A daily reminder: one notification a day, at the hour you pick, and only when you have not solved the puzzle yet.

Share your result after the puzzle of the day.

Playing together now survives a lost connection, and whoever you invite plays that game for free.

The notes in a cell are bigger and clearer, and the QR code scans more easily.

### 1.1 — 2026-09-24

Leaderboards and achievements through Game Center. Compare your time on the puzzle of the day, your best times and your streak with other players, and collect seven achievements along the way.

### 1.0 — 2026-09-22

No release notes.

## Apps similar to Nine

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| --- | --- | --- | --- |
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| [Sudoku AI — Coach & Learn](https://appshunter.io/ios/app/sudoku-ai-coach-and-learn/id6778964007) | — | Free | Games |
| [Sudoku: Learn the Techniques](https://appshunter.io/ios/app/sudoku-learn-the-techniques/id6787129425) | — | Free | Games |
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| [Sudoku ∙](https://appshunter.io/ios/app/sudoku/id727577974) | 4.7 (1,434) | Free | Games |
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## More apps by Balthazar Van de Velde

- [FairSwipe: Photo Cleaner](https://appshunter.io/ios/app/fairswipe-photo-cleaner/id6809029357)

All apps by Balthazar Van de Velde: https://appshunter.io/developer/6809029359

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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 2026-10-11.*