WhatsApp is an instant messenger for smartphones. It was created by company founders Brian Acton and Jan Koum. The latter was born in 1976 in Kyiv, Ukraine. In October 2014, the mobile messenger WhatsApp was acquired by Facebook for 19 billion dollars. Subsequently, Jan was appointed the executive director of Facebook, Inc. This deal was a record in the start‑up industry. The previous record‑holder, Instagram, sold for only 1 billion dollars. In April 2015, the audience of active users of WhatsApp reached 800 million.