Reversi is definitely a wonderful add-on to the collection of evergreen games for any time, any player, any device.

Rules:
The game is for two players and is being played on an 8x8 board with two sets of figures, usually distinguished by color. Being a very ancient game, it had been first played on the ground, with stones or disks. Every player picks a color to play with. The game objective is to have more discs on the table than your opponent as the game completes.

The game goes in turns. On every turn a player is allowed to put a disk of his color on certain places on the table. By doing so, he can "invert" some of the opponent's disks already in the table by closing them between his disk and another his disk, already on the table. There has to be a straight or diagonal line of opponent's disks between the new one being put on the table and another one of the same color and if there is, all those discs become "inverted".

Players are required to put disk only on a place where they can actually "caputre" at least one opponent's disk by putting it between two own ones. If a player is incapable of doing so, he loses the game.

The game starts by having two pairs of discs at the center of the table. It ends when either a player is unable to make a valid move or when the table is full. If the later, the player with more discs on the table wins.