SEOUL, April 29 (Reuters) - South Korea's Samsung Electronics Co Ltd on Tuesday reported a 3.3 percent fall in first quarter operating profit, broadly in line with earlier guidance, as returns weakened in its mainstay smartphone business.
The world's biggest manufacturer of smartphones booked a January-March operating profit of 8.5 trillion Korean won ($8.2 billion), compared with guidance of 8.4 trillion won.
Operating profit in its mobile division fell to 6.43 trillion from 6.51 trillion won in the year prior and 5.47 trillion won in the previous quarter.
Shares of Samsung Electronics, worth $220 billion, closed down 0.8 percent on Monday, compared with a 0.1 percent drop in the benchmark Korea Composite Stock Price Index. ($1 = 1035.1500 Korean Won) (Reporting by Se Young Lee; Editing by Stephen Coates)