Cell by Cell Sudoku Support

How to play

Quick Guide

1. Enter a digit: Pick a cell, then tap a digit to place it in that cell.
2. Notes mode: In Notes mode, tapping a digit writes or removes a candidate in the cell.
3. Undo and Redo: Undo cancels your last change, and Redo reapplies a change you undid.
4. Hints in an area you choose: Choose a hint area (Cell, Row, Column or Box) and ask for a hint to see Where → Why → Digit one step at a time within that area. The board changes only when you tap Fill In.
5. My Puzzles: In My Puzzles, tap Enter a New Puzzle, type the puzzle's given digits on the board or use Enter as 81-Digit Text, then tap Check Puzzle. Only a puzzle with exactly one solution can be saved, with Save and Play.

Quick fixes

Frequently Asked Questions

The hint says “There’s no hint to explain in this area right now.”

Hints support only two techniques: single candidate and hidden single. If no cell in the area you chose can be explained with them, you'll see this message. Change the area and ask again, or reason it out yourself. If you see “No cell on the whole board can be explained with the supported techniques right now.”, changing the area won't help, so reason it out yourself.

The hint asks me to check my digits.

Hints can't be given while the board has a wrong digit: when the same digit repeats in a row, column or box, or when the puzzle can't be finished from the digits entered so far. Fix the marked cells or undo your recent entries, then ask again.

My notes disappear on their own.

When you enter a digit, that digit's notes in the same row, column and box are cleared automatically. If you don't want this, turn off Settings › Notes › Auto-Clear Related Notes.

How do I turn off vibration?

In Settings › Haptics, set Haptic Feedback to Off.

Which language does the app use?

The app follows your iPhone or iPad language setting, or on Android your device language or the app's own language setting (Android 13 and later): Korean, English or Japanese. On devices set to any other language, it appears in English.

Can I move my records to another device?

There's no account or sync, so you can't move them from within the app. Records are stored only on the device and move only as part of a device backup and restore (an iOS backup, or on Android a backup to your Google Account) or a transfer to a new device. Whether they're included depends on your device settings and choices.

My puzzle won't save.

Please check the following.

• Enter at least 17 given digits.
• Only puzzles with exactly one solution are saved.
• A puzzle isn't saved if its check doesn't finish. Check the digits or enter another puzzle.
• A puzzle you've already saved isn't saved again. If you see “This puzzle is already in My Puzzles…”, continue it from My Puzzles.
• Puzzle names can be up to 40 characters. With a longer name you'll see “Puzzle names can be up to 40 characters.” and can't check or save the puzzle until you shorten it.
• My Puzzles holds up to 100 puzzles.

What happens to my records if I delete the app?

Deleting the app also deletes your game records, My Puzzles and settings from the device. There's no copy on our servers, so they can't be restored unless they're in a device backup (an iOS backup, or on Android a backup to your Google Account).