Chess

The whole game, one hand, no account. You take white against a computer opponent pitched at club-beginner level — sharp enough to take any piece you leave hanging, forgiving enough that a careful player beats it. Every rule is here, including the ones most phone versions quietly skip: castling on both sides, en passant, underpromotion, and all four ways a game can end in a draw.

How to play

You are white and you move first. Tap one of your pieces and every square it can legally move to lights up — a dot on an empty square, a ring around a piece you would capture. Tap one of those squares to play the move, or tap your piece again to change your mind. The computer replies on its own.

The highlights only ever show legal moves, so a piece that is pinned against your king simply will not offer the squares that would expose it, and when you are in check the only moves offered are the ones that get you out. Your king's square glows red while it is under attack.

Castling is played by moving the king two squares towards the rook — the rook jumps across by itself. En passant appears as a normal diagonal pawn move onto an empty square. When a pawn reaches the far rank a small picker asks which piece you want; queen is usually right, but rook, bishop and knight are all there, because underpromotion to a knight is occasionally the only way to deliver mate or to avoid forcing a stalemate.

A game ends in one of six ways. Checkmate either way, and four kinds of draw: stalemate, when the side to move has no legal move but is not in check; insufficient material, when neither side has enough left to mate; the fifty-move rule, after fifty moves each with no capture and no pawn move; and threefold repetition, when the same position with the same rights comes up three times. Checkmating the computer adds one to your streak, a draw keeps it where it is, and getting checkmated puts it back to zero.

Tips & strategy

Get your knights and bishops off the back rank before you go hunting. Two or three central pawn moves, both knights and both bishops out, then castle — that is the whole opening, and it is worth more than any trap you might have memorised. A king still sitting on e1 on move fifteen is the single most common reason a casual game falls apart.

Before every move, look at what the computer's last move now attacks. Engines at this level do not plan deeply, but they never miss a piece you leave hanging, and almost every loss to a weak engine is a piece given away rather than a combination missed. The habit of asking "what does that move threaten?" is worth more than any amount of opening study.

Trade pieces when you are ahead in material and avoid trades when you are behind. Being a knight up in a position with everything still on the board is worth much less than being a knight up with only kings and pawns left, because the extra piece has fewer defenders to work around. The same logic in reverse means that when you are down material, keeping pieces on gives you chances to complicate.

When you are winning easily, watch for stalemate — it is the classic way to throw away a won game. If the computer has only a king left and no legal move, the game is a draw no matter how many queens you have. Give the enemy king a square to breathe, bring your own king up to help, and mate with the rook or queen supported rather than trying to trap it in a corner by force.

On a phone the board is small, so tap the piece first and read the dots before you commit. The highlights are generated from the same legal-move code the rules use, so if a square is not lit the move genuinely is not legal — a pinned knight that seems like it should be able to jump really cannot.