Earnings reports from Samsung Electronics Co. and Sony Corp. underscore the two Asian technology companies’ increasing reliance on components sales to drive profits as it becomes harder to earn money selling smartphones and other consumer electronics.

Samsung, the world’s largest smartphone maker by sales, on Thursday posted an 8% year-to-year drop in net profit for the quarter ended in June. Sony, Samsung’s longtime Japanese rival, said its net profit more than tripled in the quarter.

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