Picture Logic

The numbers beside each row and above each column tell you how many squares to fill in and in what order, so 3 1 means a run of three, a gap, then one on its own. Work out which squares must be filled and which must be empty - you never have to guess - and a picture appears when you are done.

Sixty-four squares. The numbers beside each row and above each column tell you how many squares in that line are filled in, and in what order. 3 1 means a run of three filled squares, then at least one empty square, then one filled square on its own. Fill in the right ones and a picture turns up.

Working out one line

Say a row is eight squares wide and its clue is a single 5. You do not know where the five sit, but you know something anyway. Push them as far left as they go, and then as far right as they go:

■■■■■□□□ as far left as they go
□□□■■■■■ as far right as they go

The fourth and fifth squares are filled in both times. Whichever way the run actually sits, those two are filled - so you can fill them in now, and you have not guessed anything. That is the whole game: find the squares that come out the same every way the numbers can fit, fill those in, then look again with what you have just learned.

Every picture in this game can be finished this way. If you are stuck, there is a square you can work out somewhere - you never have to try one and see.

Filling and marking

Tap a square to fill it in. Tap it again to rub it out. Switch to Mark empty and a tap puts a small × in the square instead: that is how you write down a square you have worked out cannot be filled. Marking is worth doing. A row with two squares crossed off is a much easier row to read than one with two squares you are only remembering about.

A clue goes faint once the filled squares in its line match it, so you can see at a glance which lines you have finished. It does not say they are in the right place - two lines can both match 2 1 and only one of them be right.

On a keyboard

Tab into the board, then the arrow keys move around it, space uses whichever tool is switched on, X marks a square empty whatever the tool says, and backspace clears the square you are on.

When you get stuck

Check tells you how many squares you have filled in that should not be. It does not say which ones - that is still yours to find - but it does tell you whether the thing you are stuck on is a mistake you already made. Clear empties the board and starts the same picture again.

There is a new picture every day, and everyone playing on this device gets the same one. Once you have done today's, Practice gives you a different picture that does not count towards your streak.

Touch: tap anything on the board to use it. Every button and key is at least 44px tall, so it works with a thumb. The squares of a board are as big as the screen allows - on a small phone some of them are smaller than that, which is why the keys and the number pad, not the squares, are what you type with.

Keyboard: Tab moves between the controls and Enter or Space activates the one you are on. That covers the buttons the game screen always has - Pause, Restart and this page's link - as well as anything the board adds.

Pause stops the clock and freezes the board; Restart gives you a fresh one.

Your score is how long you take, in minutes and seconds. Lower is better.

There is one new puzzle a day, the same one for everybody on this device, and playing on days in a row builds a streak. Once today's is done you can practise as much as you like.