Stockfish Chess

Strong free chess program. Features: * Free, but much stronger than most commercial iPhone chess apps! * Plays aggressive and dynamic chess, and is not afraid of sacrificing material for initiative or attacking chances. * Adjustable playing strength. * Choose between several styles of play: "Passive", "Solid", "Active", "Aggressive" or "Suicidal". * Big, deep and varied opening book. Choose between three levels of book variety. * Displays book moves and engine analysis, including search depth, evaluations and main lines. * Allows you to easily set up board positions. * Able to think during the opponent's time, for maximum playing strength (disabled by default, in order to save battery life). * Supports saving and loading games to PGN files, sending games by e-mail, and transferring PGN files between your device and your computer. * Play against the machine, or play both sides, with or without book moves and engine analysis displayed on the screen. * Choose from nine piece sets and eight color schemes. * Complete source code available under the GNU General Public License.