CUPERTINO (AP) — Apple Inc. shook up its executive ranks Monday, saying the head of its store operations is leaving after just six months on the job and the long-serving head of its iPhone software development operations is exiting next year. Apple didn't say why retail senior vice president John Browett and iOS software SVP Scott Forstall were leaving, but both have presided over missteps this year. Browett cut staffing hours at Apple's retail stores, a move the company reversed and acknowledged as a mistake.