WhatsApp, the world's most popular instant messaging service, is bigger than most social networks (except Facebook). The service has added over 30 million users in the last month, taking their tally of monthly active users, up from 400 million in December to 430 million in January. Each day, over 50 billion messages are sent and received (phew, people sure do chat a lot). Also, the company revealed that 35 million of the users belong from India.
At this rate of growth, it is predicted that WhatsApp will have 500 million users by the end of Q1 2014.