The trending phone application, WhatsApp, now has more than 400 million monthly users.

That is a 50 million increase from what the messaging service reported in October, according to Forbes. While the app has not quite passed Facebook’s 1.2 billion users, WhatsApp has certainly grown substantially in the short amount of time the service has been around.

The app has, however, passed Facebook up in one aspect, according to The Business Insider. WhatsApp sends 20 billion messages a day. That is approximately double the size of Facebook’s messaging traffic.

WhatsApp was created in 2009 by two former Yahoo! employees. The app allows a user to send text messages, audio messages, and video to others. The app is also free for the first year of use, then only a $1 a year fee is applied.

WhatsApp has plenty of competition to keep up with. Jan Koum, founder of WhatsApp, has one goal for the company, and that is to be a way of simply communicating for its users.

As long as that service remains necessary, Koum believes that the company will continue to grow with its competition.