That's because WhatsApp for Android now automatically safeguards messages with end-to-end encryption to help protect users from hackers and surveillance.
Given everything that users of Snapchat and other mobile services have suffered recently, this is probably a good idea.
That said there are a few catches, like the fact that only text messages sent between two Android devices will be encrypted. That means no media or group messages, and no iOS users.
Sorry, Johnny Law
But on the plus side Facebook-owned WhatsApp says it can't help law enforcement and governments decrypt the contents of these messages even if it wants to, which should please users while pissing off Big Brother - never a bad thing.
WhatsApp is encrypting its messages with help from Open Whisper Systems, which said in a blog post that it plans to eventually bring the encryption to WhatsApp apps on other platforms as well.