Othello is played on an 8×8 board with black and white discs. Place a disc so that it sandwiches your opponent's discs between your own, flip them to your colour, and the player with more discs at the end wins. The rules are simple, but the game is deep.
History of Othello
Othello comes from the 19th-century English game Reversi. The rules were later refined in Japan, and it was released by Tsukuda as “Othello” in 1973. Its name is said to come from Shakespeare's play Othello, reflecting the black-and-white conflict.
Rules
Place a disc on an empty square so that it sandwiches one or more opponent discs in a straight line (horizontal, vertical, or diagonal) between your disc and another of your discs, then flip the sandwiched discs.
If you have no legal move, you pass.
When both players pass in a row, or the board is full, the game ends. The player with more discs wins.
Features of Hanako's app
Legal moves are shown, hints are available, there are three difficulty levels (easy, normal, hard), undo is available, and a game record is kept.
Five tips for beginners
Corner squares can never be flipped, so they are the most valuable.
Do not carelessly take a square next to an empty corner — it may let your opponent take the corner.
Do not flip too many discs early in the game.
Reduce your opponent's mobility: fewer moves for them is good for you.
Count the discs in the endgame.
Start on easy against Hanako and get used to the game gradually.