Kakao's business model history is actually rather fascinating, and they keep grabbing sizeable market shares in unlikely or previously inexpressive markets to great success.

> In 2012, KakaoTalk's $42 million revenue is broken down to 67.5% ($31.1M) gaming, 26.2% ($12.1M) advertising, and 6.3% ($2.8M) emoticon sales. [1]

[1] https://en.wikipedia.org/wiki/KakaoTalk#Company_Business_Mod...