A fresh take on
logic grid puzzles.
If you love Sudoku, binary puzzles, or Takuzu, get ready for a fresh mental workout. DUO takes the classic logic grid concept and refines it into a sleek, modern experience designed to test your deductive reasoning and spatial intelligence.
How it works
Every move is a balance.
Your goal is to fill the grid with symbols (Hearts, Spades, Diamonds, Clubs) while obeying three strict rules. No math required, just pure logic.
No three in a row
You cannot place three or more of the same suit next to each other, horizontally or vertically. Similar to Takuzu and binary puzzle rules.
Balance every line
Each row and column must have equal counts of each symbol. A 6x6 Classic grid needs exactly 3 hearts and 3 spades per line.
Satisfy the markers
Constraint markers between cell pairs tell you if two neighbours must match or differ. Use them to chain deductions across the grid.
Game features
More than just a puzzle game.
Classic and Quad modes
Classic uses 2 symbols for a zen binary puzzle experience. Quad steps up with 4 symbols and new constraint types for expert-level logic.
Infinite logic challenges
From quick 4x4 warm-ups to massive 12x12 expert grids. Whether you have 2 minutes or 2 hours, there is a level for every mood.
Deep statistics and streaks
Track your brain training journey with detailed stats. Monitor your daily streak on the calendar and race against your best time across all difficulties.
Smart solving tools
Don't guess, deduce. Use Notes to track possibilities before you commit. Stuck on a pattern? Smart Hints and Error Highlighting help you break through.
Customize your experience
Unlock themes like Sunset, Forest, and Neon. Choose board styles from Minimal to Glass. Toggle Select and Place mode for speed or classic tapping for precision.
Works offline
No internet needed. Your puzzles, progress, and statistics are all stored locally on your device. Play anywhere, anytime.
A gym for your brain.
Perfect for fans of Sudoku, Takuzu, and grid puzzles who want a clean, minimalist experience without the clutter. Do you have the logic to balance the grid?