Over the past year, Apple's iPhone has been struggling in South Korea with sales down to nearly 1/3 what they were the previous year. 

Although Apple is still the number one foreign smart phone manufacturer operating in Korea compared to Motorola, Sony, HTC, Nokia, and Blackberry, which each having <1% market share, Apple is feeling the pressure from domestic manufacturers like Samsung, LG, and Pantech.  Since 2010, Samsung's market share has risen to a commanding 65% while the two other Korean manufacters, Pantech and LG, have each grown to 15%.  During this same period, Apple's market share has dropped from 23.2% down to 3.2%.  
Although Apple does have reasonable sales with the iPad, iPod, and Macbook, these sales are still at a much smaller scale compared to smart phone sales.