The hardest board games for a computer to beat a human is the Chinese game Go, and recently Google’s AlphaGo beat the world champion twice in a row.  Because of the sheer number of possible moves in Go, computer scientists thought until recently that it would be a decade before a machine could play better than a human master.

Chess is a little simpler; people have been studying this problem since the 1970’s and in today’s world, the best computer programs almost always win.  The original chess programs worked by evaluating all possible moves, and looking ahead 5 or 6 moves, to come up with the best possible move.  While this “brute force” method took a lot of time – especially on older slower computers – it lead the research in early artificial intelligence.
Looking ahead several moves and trying every possible move is how a computer can beat a human playing the game Connect 4. Players take turns dropping their colored discs from the top into a seven-column, six-row vertically suspended grid. The pieces fall straight down, occupying the next available space within the column. You win when you form a horizontal, vertical, or diagonal line with four of your colored discs.
Using the “look-ahead” strategy, your computer opponent in Blindfold Connect will always win.  Losing the game time after time makes for a sad experience, so I tweaked the game so your opponent occasionally makes a mistake.  In addition, you can adjust the skill of your computer opponent; a beginner opponent plays randomly and the moderate opponent looks ahead about four moves.  The expert opponent looks ahead 10 moves, and selects the move that leads to the highest number of good outcomes.
To start playing Blindfold Connect, press here:
https://itunes.apple.com/us/app/blindfold-connect/id1214900307?mt=8