Digital 2014: WhatsApp Reaches 600 Million Users
For context, WhatsApp only just passed the 500 million mark back in April, which means the service is currently growing by an astonishing 800,000 new active users every day - that's more than 9 every second.
WeChat continues to impress too, with 438 million users, the majority of whom are still in China.
LINE and KakaoTalk also appear to be growing, although neither service reports monthly active user numbers, so direct comparisons are tricky.
This article first appeared on the We Are Social blog under a different title.