Hints and techniques

How a hint works

Tap Hint and the game finds the next logical step on your board. It explains it in stages, so you can stop as soon as you’ve spotted it:

1. Where to look: the cells or area that matter.
2. Why: the reason the move works.
3. The move: apply it with one tap, or close the hint and do it yourself.

The timer pauses while you read. Applying a hint can be undone like any other move.

Techniques the hints teach

• Naked single: a cell where only one number is still possible.
• Hidden single: a number that fits in only one cell of a row, column or box.
• Locked candidates (pointing and claiming): when a number is confined to one line inside a box, or one box inside a line, it can be removed from the rest.
• Naked and hidden pairs: two cells that share the same two possible numbers, which rules those numbers out elsewhere.

On the hardest puzzles you may reach a position these techniques don’t cover. The hint will tell you so rather than guess.

Auto candidates

Turn on Auto candidates in the game menu to fill every empty cell with the numbers still allowed by its row, column and box. They refresh whenever you place or erase a number. Turning it off keeps your current notes.