The Globe and Mail reports in its Tuesday edition that Tim Cook, Apple's chief executive officer, said Monday he is stepping down after nearly 15 years running an operation that rode the wild popularity of the iPhone to become one of the most influential and valuable companies in the world. A New York Times dispatch to The Globe says Mr. Cook, 65, will move into a new role as Apple's executive chair in September and be succeeded by John Ternus, the 50-year-old head of Apple's hardware engineering. Mr. Cook's resignation will end one of the most successful management runs in the history of U.S. business. During his tenure, Apple's annual profit quadrupled to more than $110-billion (U.S.), while its value ballooned more than 10-fold to $4-trillion (U.S.). Mr. Cook replaced Apple co-founder Steve Jobs shortly before Mr. Jobs's death in 2011, having earned a reputation for perfecting the nuts and bolts of a global consumer electronics business. Apple has since defined how a modern technology company operates, with products assembled in a supply chain that stretches from the giant operations that Mr. Cook helped create in China to India and Brazil and a popular retail business that operates on five continents.