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Are you familiar with terms like "X-Wing", "2-String Kite", or "Locked Candidates"? If yes, Smart Sudoku is for you. If not, even more so.

Unlike most Sudoku apps, Smart Sudoku helps you solve tough puzzles by not simply revealing cell solutions, but by giving you professional tips. It tells you what patterns to look for in order to eliminate candidates.

Smart Sudokus's unique scoring system ranks your solution not by the time you spent, but by how efficiently you solved the puzzle.

Smart Sudoku comes with hundreds of challenging puzzles built-in. Copying a puzzle from a newspaper is a breeze - think of typing in a few phone numbers.

If you rate solving a Sudoku puzzle higher than watching cute animations and listening to funny sounds, then Smart Sudoku is what you've been looking for.

"Excellent. Very simple to enter puzzles from the newspaper. Candidate numbers are displayed, allowing solutions to really tough puzzles to be solved without the laborious job of setting up candidates." (UK user)


• Powerful hint system based on the most important solving strategies
• Very fast manual puzzle entry method (typically 40 seconds or less)
• Multiple squares may be handled simultaneously
• Show or hide candidates anytime while solving the puzzle
• Innovative scoring - based on efficiency of solving instead of time spent
• Copy/paste puzzles in standard text format
• Import puzzles from the Internet
• Share partially or fully solved puzzles via e-mail
• 509 puzzles built-in, from easy to almost unsolvable
• Unlimited undo/redo
• Built-in user's manual
• Landscape mode (iPad only)

Learn how to eliminate candidates by finding standard patterns. Let Smart Sudoku tell you what pattern to look for next. Still stuck? Smart Sudoku can even show you the squares and numbers involved. The affected squares are selected automatically, so eliminating candidates is a snap. Patterns handled by Smart Sudoku include:

• Naked and Hidden Singles, Pairs, Triples, Quads, and Quintuples
• Locked Candidates Type 1 and 2
• X-Wing
• XY-Wing
• XYZ-Wing
• W-Wing
• Skyscraper
• 2-String Kite
• Swordfish
• Jellyfish
• Empty Rectangle
• Unique Rectangle Type 1 and 2

Input checking
After copying a printed puzzle, Smart Sudoku will tell you whether the puzzle has a unique solution or not (usually caused by a typo or missing number.)

Efficient solving
Smart Sudoku helps you solve Sudokus in a professional way. Never add candidates, only remove them, even from multiple squares in one step. Never see candidates you eliminated reappear just because you turned candidates mode off and on. Should you ever get stuck (and no hints are available), have Smart Sudoku solve any square you wish. Or all squares for a given number. Or even the entire puzzle.

Novel scoring method
Unlike other Sudoku apps, Smart Sudoku rates your efficiency in solving a puzzle, not how quickly you do it. Solve one square at a time and your score will remain at zero. Solve as many squares as possible for a given number simultaneously and watch the progress bar grow. To get the maximum of 1000 points requires you to finish each number in a single step.

Share puzzles
Send an e-mail of a puzzle at any stage to your friends. If partially or fully solved, they'll also get the original puzzle. And, of course, they'll see your score, even a message about your making use of candidates. Recipients may paste the puzzle into their own copy of Smart Sudoku.

Puzzles from the Internet
Smart Sudoku supports the well-established text format for Sudokus (a string of 81 digits and decimal points), as well as export formats used by programs like HoDoKu and Simple Sudoku, giving you access to thousands of puzzles available on the Internet. Just download the text strings and paste them into Smart Sudoku.

iOS Store Category:

Primary: Games

Secondary: Puzzle

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Smart Sudoku screenshot 1Smart Sudoku screenshot 2Smart Sudoku screenshot 3Smart Sudoku screenshot 4Smart Sudoku screenshot 5

Version History

Launched Aug 25, 2011 (over 9 years ago).

Releasing new versions every 9 months, on average.

Jan 12
Version 2.3

• Highlighting all squares containing a certain number as a candidate now also works when candidates are shown

Nov 05
Version 2.2

• When solving, tap any number to highlight all squares that have that number as a candidate (thanks, Chris, for suggesting this)

• Difficulty level is shown for built-in puzzles (from "Easy" to "Extreme")

• Added 10 puzzles (#500..509) considered to be unsolvable by applying known strategies

• Pasting puzzles into the top text field handles additional text formats, including grid layout and HoDoKu library format

• Compatible with current iOS versions and devices


• Removed duplicate puzzles

Sep 02
Version 2.1

• If audio is playing on start-up, Smart Sudoku will not produce any sounds
• Added 30 new puzzles (for a total of 499)

Dec 19
Version 2.0

• Change background pattern (triple-tap background)
• Sound volume is now stored inside app
• More puzzles
• Fixed issue resulting in empty puzzle picker on iPhone (iOS 8 only)

Aug 23
Version 1.8

• Added 20 new puzzles
• Bug fixes

Sep 14
Version 1.7

• Added 40 new puzzles
• Full-screen display
• New app icon
• Compatible with iOS 7
• Requires iOS 5.1 or later

Sep 20
Version 1.6

• Supports iPhone 5 screen
• Compatible with iOS 6
• Added 50 hard puzzles (#350...399)
• Fixed possible crash while entering a puzzle

Mar 18
Version 1.5.2

• Improved selecting/unselecting of squares

• Supports iPad retina display

Oct 31
Version 1.5.1


• "Unselect" button was disabled in certain situations when it shouldn't have been
• Fixed crash in "2-String Kite" pattern detection (iOS 5 only)

Minor user interface enhancements

Oct 15
Version 1.5.0


*** Introducing HINTS ***

Now solve Sudokus like the pros! Use standard patterns to solve even tough Sudokus (see app description).

Also in this update:
• Additional solve options: single square, all squares of a number, or entire puzzle.
• High-score for built-in puzzles is now shown on both iPhone and iPad.
• 100 new puzzles added.
• Ultra-hard puzzle #250 for the really ambitious.

Aug 25
Version 1.0.1

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