Connect Four

Take turns dropping a disc into a column; it falls to the lowest free row. The first player with four of their own discs in a line - across, down or diagonally - wins. Play someone next to you, or the computer at three levels.

Discs fall. Pick a column and yours drops to the lowest free space in it - you choose the column, gravity chooses the row.

Four of your own discs in a straight line wins: across, straight down, or along either diagonal. The diagonals are the ones people miss, so it is worth looking along them before every move - your own and theirs.

If all 42 spaces fill up and nobody has a line, it is a draw. Nobody loses a draw.

Two players take turns on the same phone; the bar above the board always names whose turn it is and shows their colour. vs. Computer gives you an opponent at three levels. Every level will take a win it can see and block one of yours - Easy just does not look very far ahead, and Hard looks six moves deep.

The best trick in the game is a move that makes two lines of three at once. Your opponent can only block one of them.

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. Both players use the same device, taking turns - whose turn it is is always named on screen.

Your score is how many moves you take. Fewer is better.

Play as often as you like. Every game is saved on this device, and your best turns up on the scoreboard.