As documented in earlier posts, Cyworld was once South Korea's leading social media platform and was wildly popular with young people in this country. It had over 30 million users at its peak popularity. Earlier this month, as reported by The Korea Times, it suddenly closed down its operations in Korea, without advance notice to users or the public. As reported by the Korea Joongang Daily, Cyworld had already closed down its international arm in 2014 (click on the graphic for a full size version). A major cause of Cyworld's demise was its failure to adapt to the mobile revolution. That failure, in turn, may have been exacerbated by the two and one half year delay in allowing Apple's iPhone into the Korean market, a topic explored in this blog and my recent books (with Myung Oh).