WhatsApp just announced that its messaging app is now used by 500 million people around the world. And those are all described as "regular, active" users, another sign of the company's soaring growth — and the loyalty of its community. When Facebook announced plans to acquire WhatsApp in February, the service had already crossed 450 million active users, so it's quickly jumped by tens of millions since then. The fastest recent growth has occurred in Brazil, India, Mexico, and Russia, according to WhatsApp.

Selling to Facebook hasn't slowed growth much

The milestone is significant since it's halfway to the "goal" that Mark Zuckerberg mentioned when announcing the massive buyout. "WhatsApp is on a path to connect 1 billion people," Zuckerberg said in mid-February. "WhatsApp is the only app we’ve ever seen with higher engagement than Facebook itself." The speedy and steady growth that WhatsApp has enjoyed since launch is seen as a major factor in Facebook's decision to spend billions in cash and stock for the company.

"Our users are also sharing more than 700 million photos and 100 million videos every single day," said WhatsApp founder Jan Koum. But it appears his team won't be taking much time to celebrate, with Koum adding, "Here at WhatsApp, we’re just getting started."