WhatsApp, an alternative texting app for smartphones, announced today that it now has 400 million people using the service per month. It has even more people registered for the app.
That’s bigger than Twitter, which has 230 million active users and just had its big IPO.
WhatsApp is a messaging service that doesn’t require users to pay for texts. Instead, messages are sent over the Internet. It’s particularly popular overseas where carriers typically charge users for every text message sent. The app is found on iPhone, Android, Windows Phone, and BlackBerry.
In the mobile messaging space, for example, Kik Interactive said last week it now has 100 million users. Line last month said it had 300 million. WeChat, which is owned by Chinese Internet conglomerate Tencent, is very popular in China and has about 300 million users.
“We want to steer the conversation to be about active users, not registered users,” said WhatsApp CEO Jan Koum. “We’re a bit fed up and frustrated about people talking about registered users. We think it’s important for us as a leader in the space to speak up and be ethical.”
WhatsApp users now send 16 billion messages per day. Also, users now send 500 million images per day (more than Snapchat).
Mountain View, Calif.-based WhatsApp has just 50 employees. It has venture funding from Sequoia Capital and makes money from charging long-time users a dollar per year.