About Sudoku

What is Sudoku?

Sudoku is a logic-based number-placement puzzle that has captivated millions of people worldwide. The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 sub-grids contains all digits from 1 to 9.

History

While number puzzles have existed for centuries, the modern Sudoku puzzle was popularized in Japan in the 1980s by Nikoli, a puzzle company. The puzzle gained international popularity in 2004-2005 when it began appearing in newspapers worldwide.

• 1979: Howard Garns, an American architect, created the precursor "Number Place"
• 1984: Published as "Sudoku" by Nikoli in Japan
• 2004: International popularity exploded through newspaper publications
• Today: Played by millions worldwide in newspapers, apps, and online

How to Play

Basic Rules

1. Fill the Grid: Complete the 9×9 grid with numbers 1-9
2. Row Rule: Each horizontal row must contain all digits from 1 to 9, without repetition
3. Column Rule: Each vertical column must contain all digits from 1 to 9, without repetition
4. Box Rule: Each of the nine 3×3 sub-grids (boxes) must contain all digits from 1 to 9, without repetition
5. Starting Clues: Some cells are pre-filled with numbers. These are your starting clues and cannot be changed
6. Unique Solution: Each valid Sudoku puzzle has exactly one solution

Game Features

Benefits of Playing Sudoku

Tips for Beginners

1. Start with Easy Puzzles: Build your skills and confidence gradually
2. Use the Notes Feature: Mark possible numbers in empty cells (pencil marks)
3. Look for "Obvious Singles": Cells where only one number can fit
4. Scan Systematically: Check each row, column, and 3×3 box methodically
5. Focus on One Number: Try to place all instances of one number (e.g., all 1s) across the grid
6. Don't Guess: Use logic and deduction, not random guessing
7. Take Your Time: Speed comes with practice; focus on accuracy first
8. Use Hints Sparingly: Try to solve puzzles independently to improve faster

Advanced Strategies

As you progress, you'll learn advanced solving techniques:

Naked Pairs/Triples

When two or three cells in a row, column, or box can only contain the same two or three numbers, you can eliminate those numbers from other cells in that group.

Hidden Singles

A number that can only go in one cell within a row, column, or box, even though that cell has multiple candidates.

Pointing Pairs

When a number appears as a candidate in only two cells of a box, and those cells are aligned in a row or column, you can eliminate that number from other cells in that row or column.

X-Wing Technique

An advanced pattern where a number appears as a candidate in exactly two cells in two different rows (or columns), forming a rectangular pattern.

Swordfish Pattern

Similar to X-Wing but involves three rows and three columns, creating a more complex elimination pattern.

About This App

Our Mission

We created this Sudoku app to provide a clean, enjoyable puzzle-solving experience that helps people train their minds while having fun. Whether you're a complete beginner or a seasoned Sudoku expert, our app offers the right challenge for you.

Key Features

• Clean, intuitive interface designed for mobile devices
• Offline play - solve puzzles anywhere, anytime
• Auto-save - never lose your progress
• Helpful tools without making the game too easy
• Daily challenges to keep you engaged
• Statistics to track your improvement over time

Credits and Acknowledgments

Sudoku by BRTeam is built with the following technologies:

• AngularJS: Frontend framework for smooth, responsive UI
• Apache Cordova: Cross-platform mobile development
• SQLite: Local database for offline storage
• OneSignal: Push notification service
• Google AdMob: Advertising platform

Special thanks to the Sudoku community worldwide for making this timeless puzzle game beloved by millions.

Support and Feedback