Gridsolve

GridSolve is a clean, ad-free classic Sudoku puzzle game. Every single puzzle
is generated fresh on your device and verified to have exactly one valid
solution before you ever see it — no guessing games, no dead ends, just
real logic-driven Sudoku. No account, no ads, no internet connection
required.

HOW TO PLAY
- Fill the 9x9 grid so every row, column and 3x3 box contains the digits 1
through 9 exactly once.
- Tap a cell to select it, then tap a number on the pad to fill it in.
- The selected cell's row, column and box are highlighted automatically, so
you always see what's already ruled out.

FOUR REAL DIFFICULTIES
- Easy, Medium, Hard and Expert puzzles, tuned by the number of starting
clues — from a gentle ~40+ givens down to a sparse 24-26 for Expert.
- Every puzzle at every difficulty is generated with a randomized
backtracking algorithm and checked with a solver to guarantee a unique
solution, regardless of how sparse it looks.

FEATURES BUILT FOR REAL SOLVERS
- Notes / pencil-marks mode — jot small candidate numbers into any cell
without committing to an answer, exactly like solving on paper.
- Optional conflict highlighting — instantly see cells that clash with the
same number in their row, column or box.
- Optional same-number highlighting — shade every cell that already holds
the number you've selected.
- Hints — reveal the correct value for your selected cell (or the next
empty one) when you're stuck, with hints-used tracked per puzzle.
- Undo — step backward through your move history, including note toggles
and erases, not just final answers.
- A live timer for every puzzle, with your best time saved per difficulty
so you can chase a personal record.

STATS THAT STAY ON YOUR DEVICE
A dedicated Stats screen tracks puzzles completed and best time for each
difficulty, your total puzzles played, and your current daily play streak
— all stored locally, never uploaded anywhere.

FOUR APPEARANCE MODES
Choose System, Light, Dark, or a pure Black & White theme for maximum
contrast and battery savings on OLED screens.

PRIVACY BY DESIGN
GridSolve works completely offline. There is no account, no sign-in, no
ads, and no analytics or tracking of any kind. Your puzzles, notes,
settings and stats are stored only on this device, and you can clear them
at any time from Settings.

Whether you're a casual solver working through Easy puzzles on a coffee
break or an Expert-level regular chasing your best time, GridSolve is a
quick, focused, genuinely-fair Sudoku experience that respects your time,
your data, and your battery.

CATEGORY
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Puzzle

SUGGESTED TAGS
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sudoku, puzzle, number puzzle, logic game, offline game, brain game, pencil
marks, notes, single player, no ads, casual, classic sudoku