How a K-pop translation app became Big Tech's data supplier

In July 2013, with "Gangnam Style" past a billion views on YouTube and still climbing, Psy sent his global followers to a tiny Seoul startup: "Use flitto.com to read my tweets in your own language." Flitto was then a small Seoul-based translation app built around K-pop fans translating celebrity posts for reward points.

K-pop gave the young service a ready-made global community.

Thirteen years later, the app is a Kosdaq-listed artificial intelligence company whose largest customers are US techno ...