Fill every square so that each row, each column and each box has every symbol in it exactly once.

There is no adding up. The numbers are just shapes — that is why the little size uses pictures instead.

Tap a square, then tap what goes in it. Tap the same one again to rub it out.

The squares that came with the puzzle are darker and cannot be changed. The ones you filled in are yours.

If you put something where it clashes with another one, both turn red. That is not the answer — it is just checking you would have done yourself.

Tap ✏️ to make little pencil marks instead, for the maybes.

💡 fills in one square that can be worked out right now, and picks the easiest one it can find.

Nothing is timed against you.