Out of the 27 billion messages, 10 billion of these were inbound from WhatsApp users, with 17 billion messages received. These figures do not really tally because they do include group messages, hence to send one message into group chat that comprises of 10 people would be considered as 1:10 inbound:outbound. Where do you think Whatsapp is headed after this particular milestone?
In order to generate this seeming insane amount of message volume, WhatsApp CEO Jan Koum shared that there is over 200 million active monthly users, which would certainly make them larger compared to Twitter, hence it would not be too far fetched to consider them as the leader in the mobile messaging industry right now.