San Francisco Giants catcher Buster Posey is the first Major League Baseball player to develop and market his own official mobile game, offering a free game called "Buster Bash" for Apple (AAPL) mobile devices. The game, available in Apple's iTunes store Monday morning, offers fans the chance to mimic Posey's path to the majors -- from hitting whiffle balls in the backyard of his boyhood home in Georgia to playing in the big leagues.