Facebook’s WhatsApp messaging service now has 2 billion users worldwide, the company announced in a blog post today, up from 1.5 billion and 1 billion users in 2018 and 2016, respectively. That compares to 2.5 billion users for Facebook itself, according to The Wall Street Journal, and 1 billion Instagram users (although that number is from June 2018).

WhatsApp used the milestone to reiterate the importance of encrypting its users’ messages, a practice that is coming under increasing amounts of pressure from lawmakers around the world. Governments argue that being unable to read people’s messages makes it harder to discover when the messaging app is being used to facilitate terrorism, child exploitation, and other crimes.

“For all of human history, people have been able to communicate privately with each other.”

WhatsApp CEO Will Cathcart says that the company has no plans to disable encryption on its service. “For all of human history, people have been able to communicate privately with each other, and we don’t think that should go away in a modern society,” he told The Wall Street Journal. However, the CEO added that WhatsApp will provide metadata when it is useful for an investigation.

In the future, Cathcart told the WSJ that the company is working to make the service interoperable with Facebook’s other messaging clients in plans announced by Facebook CEO Mark Zuckerberg last year. However, Cathcart admitted this integration may have its limits, with some features that are present on a messaging service like Messenger not translating into WhatsApp.