WhatsApp has hit 800 million monthly active users, according to a tweet from founder Jan Koum, indicating the company is maintaining its rapid growth trajectory.

Early this year Koum put the figure at 700 million, while the 600 million mark was passed in August 2014 – indicating that it is not seeing any slowdown of demand.

The Wall Street Journal noted that the messaging app is on track to hit one billion active users by the end of 2015 – putting it comfortably ahead of its closest rivals.

WhatsApp has had a busy year, adding the long-anticipated support for voice calling to its app, in order to broaden its portfolio to better rival players such as Skype, Viber, and Appe’s FaceTime.

The company has also introduced a web-based version of the service, although unlike other competing products, it is paired with a smartphone app.

Separately, it was reported that the company is working on Google Drive integration, to enable copies of messages and multimedia to be stored using the cloud storage service.