Koum was notoriously untrusting, after growing up under surveillance by the USSR in Ukraine. He built an app that was end-to-end encrypted, so the records of what people were saying to each other weren’t readable by anyone—not the police, and not even his company. He promised his users “no ads, no games, no gimmicks,” just a simple tool they could pay $1 a year to use. It would be a stretch to join Facebook, where surveillance of users powered the advertising engine.
