Pencil Sudoku: Variant Puzzles

Solve sudoku the way it was meant to be solved: with a pen in your hand.

Pencil Sudoku is built around Apple Pencil. Write your digits and notes directly on a paper-like board, and the app reads your handwriting - learning YOUR handwriting as you play, so recognition keeps getting better. No keyboard between you and the puzzle. Prefer tapping? A complete touch mode is built in, and on iPhone the whole app is designed for it.

43 PUZZLE TYPES
Classic sudoku plus a deep library of variants: Killer, Thermo, Kropki, XV, Windoku, Irregular, Diagonal, Arrow, Renban, German Whispers, Palindrome, Skyscraper, X-Sums, Little Killer, Clone, Fortress, Odd-Even, Quadruple, Mathrax, Greater Than, and many more — over 300 puzzles, organized by family so you can find your favorites.

MADE FOR SOLVERS
• Handwriting recognition that adapts to you — private, on-device, never uploaded
• Every note style: corner, center, grid, and Snyder notation
• Draw links between candidates for chains and coloring techniques
• Bookmarks and rewind to explore bifurcations without losing your place
• A customizable favorites bar — your tools, your colors, your layout
• Digit spotlight, number lock, and completion shading for fast scanning

HELP ONLY WHEN YOU WANT IT
Hints escalate gently and never judge — from a nudge toward the right area to a full technique walkthrough. Every assist can be switched off. The app never fills in a cell for you.

EASY ON THE EYES
A warm, paper-like board designed for long sessions.

YOUR DATA STAYS YOURS
No accounts, no tracking, no data collection. Your handwriting model lives on your device.

Start free. One simple one-time purchase unlocks unlimited play — no subscription, ever.