From wired.com
DISAPPEARING OR EPHEMERAL messaging has become a popular feature on social networks like Snapchat and privacy-focused communication apps like Signal, Telegram, and Wire. It doesn’t stop the people you’re chatting with from taking screenshots of your chats or otherwise logging them, but it makes it less likely that your old messages could come back to haunt you in unforeseen ways. Now WhatsApp, one of the biggest platforms in the world to offer end-to-end encryption by default for all its chats, is launching a version of the feature. But it has some limitations.