Four Wins – Four in a Row

Connect Four as you know it — only with an opponent that really thinks. The classic board game, also known as Connect 4 or Four in a Row, as a strategy game for one or two players. No account and no sign-in: just you against the machine, two of you taking turns on the same screen — or over the net against someone else. Behind the machine there is no random number generator but a negamax search with alpha-beta pruning, move ordering from the centre outwards and a transposition table. On the highest level it searches iteratively as deep as it manages in 1.4 seconds — about thirteen plies on an empty board. Beating it takes planning ahead. FOUR DIFFICULTY LEVELS • Easy — searches two plies and blunders on purpose. For in between. • Medium — four plies, the occasional mistake. • Hard — seven plies, no slips. • Unbeatable — searches until the time is up. The level can be changed at any time, even mid-game. TWO PLAYERS OR OVER THE NET Two people can take turns on one device. The hint stays off in that mode, because both of you are looking at the same screen, and those games do not count towards the statistics. Over the net, one side creates a game and passes on the six-character code, the other joins with it. Only the moves travel — no name, no account, no identifier of your device. HELP THAT EXPLAINS • Threats — a green ring shows where you win on the next move, a red one where the machine wins. Switch them off once you see them yourself. • Hint — names a column and the reason: an immediate win, a forced block, a double threat, a necessary sacrifice or a solid build-up. The move is still yours to play. • Undo — takes back your move together with the machine's reply. Ideal for re-checking a line you were unsure about. • History — the whole move order below the board. After a loss you can see where it turned. STATISTICS Wins, losses, draws and win rate, plus current and longest win streak and the fastest win — broken down by difficulty. All on the device, deletable in one step. FOR IPHONE, IPAD AND MAC • On the iPad and the Mac, board and controls sit side by side • On the Mac with a menu bar and shortcuts: new game, undo, hint and the seven columns • Light, dark or follow the system • Nine colour schemes, and the board stays gold against steel • German and English, switchable independently of the device language NO CATCH Against the machine or with two players, the app sends nothing; the search always runs on the device. It uses the network only for games against other people. No ads, no accounts, no analytics, no purchases. Statistics and settings live on the device and disappear with the app. A small game that takes its opponent seriously.