Messaging app WhatsApp's founder Jan Koum has announced that the service has reached a new high of 700 million users, who are now sending 50 billion messages daily, which is higher than global SMS market.

With WhatsApp-ing now bigger than texting, all eyes are on how the messaging app space will evolve this year, and also how WhatsApp will integrate with Facebook, its owner, now that it is such a formidable force in its own right.

In this graph, published by Business Insider, WhatsApp's meteoric growth can clearly be seen.

In a recent media interview, WhatsApp's founder said he is aiming for one billion users - now that would be almost the size of Facebook, its parent. Brands should be watching developments here closely, along with the developments across the entire messaging apps space.