Gridline: Logic Puzzles

Gridline brings the classic logic puzzles from the back page of the newspaper together in one calm app. Every puzzle is made on your phone, has exactly one solution, and can always be solved by logic alone. You will never be forced to guess.

FOUR PUZZLE TYPES, THREE DIFFICULTIES EACH
• Nonogram, also known as Picross, Hanjie, Griddlers, Picture Cross or paint-by-numbers: use the number clues to fill the grid and reveal a hidden picture.
• Killer Sudoku, sometimes called sum sudoku: classic 9×9 sudoku, but with cages whose digits add up to a total instead of starting numbers.
• Binairo, also known as Takuzu or the binary puzzle: fill the grid with zeros and ones, never three alike in a row, with every row and column different.
• Futoshiki, also called Unequal or More or Less: place each number once in every row and column so that every inequality sign holds.

A DAILY PUZZLE
A new puzzle of each type every day, the same for everyone, with a streak to keep going.

HINTS THAT TEACH
Stuck? A hint shows the next logical step and names the technique behind it, or points out a mistake. It never just fills in the answer.

MADE FOR COMFORTABLE PLAY
• Plays offline, anywhere. No internet connection needed to play, and no account.
• Pick up where you left off: every move is saved, with full undo and redo.
• Large, clear grids, pinch to zoom on big puzzles, light and dark themes, large text and TalkBack support.
• Personal best times and daily streaks for every puzzle type.
• Mistake marking is off by default, and yours to switch on.
• In English, German, French, Spanish and Brazilian Portuguese.

Gridline is free to play and supported by ads that stay out of the way: never a full-screen ad in the middle of a puzzle. A single purchase removes the banner and the ads between puzzles.