Looks like WhatsApp is battening down the hatches.

Facebook Inc.’s messaging service announced Tuesday it has strengthened its existing security features and introduced full end-to-end encryption in its latest version of the app.

According to WhatsApp, the update will apply to every call made and every message sent – including photos, videos, files, and voice messages – through the service.

WhatsApp said the messages will be secured with a lock that can only be opened by the sender and recipient, meaning only the user and the person they’re communicating with can access the content. Additionally, each message will have its own unique lock and key, WhatsApp said.

Those using the newest version of the app won’t have to go fishing for the feature, either: WhatsApp said end-to-end encryption will be enabled by default.

WhatsApp first began encrypting its messages in 2014.

In a blog post introducing the expanded feature, WhatsApp founders Jan Koum and Brian Acton said encryption is “one of the most important tools governments, companies, and individuals have to promote safety and security in the new digital age.” That tool, they said, shouldn’t be compromised – by anyone.

“Recently there has been a lot of discussion about encrypted services and the work of law enforcement,” Koum and Acton wrote. “While we recognize the important work of law enforcement in keeping people safe, efforts to weaken encryption risk exposing people’s information to abuse from cybercriminals, hackers, and rogue states.”

Koum said WhatsApp’s dedication to protecting free, private conversation is also a personal mission for him.

“I grew up in the USSR during communist rule and the fact that people couldn’t speak freely is one of the reasons my family moved to the United States,” he said in the post. “Today more than a billion people are using WhatsApp to stay in touch with their friends and family all over the world. And now, every single one of those people can talk freely and securely on WhatsApp.”

The shift to full end-to-end encryption comes in the context of an intense debate between government and law enforcement officials and tech companies about the place of encryption in modern justice.

Though Apple’s recent battle with the FBI over access to an iPhone used by one of the San Bernardino shooters – and the FBI’s subsequent cracking of the device and sharing of its hack technology – may have grabbed the most headlines, it’s not the only encryption case out there.

WhatsApp itself is also in a standoff with the government over access to user conversations. Thanks to encryption, the app is reportedly impossible for government officials to tap into, even with a judge’s order.