Jan Koum
Jan Koum (Ukrainian: Ян Кум, born in Kiev, Ukraine on February 24, 1976) is an American internet entrepreneur and computer engineer. He is the CEO and co-founder with Brian Acton of WhatsApp, a mobile messaging application which was acquired by Facebook Inc. in February 2014 for US$19 Billion. In 2014, he entered the Forbes list of the 400 richest Americans at position 62, with an estimated worth of more than seven and half billion dollars. He was the highest-ranked newcomer to the list that year.