Facebook released a new messaging app called Poke where users can send more complex greetings through the app, such as text, a photo or even a quick video. This real-time messages only last for up to 10 seconds. Poke app is currently only available on the iPhone.
You can now send silly or risque messages because Pokes are encrypted, and Facebook deletes the encryption keys two days after you have read the message. Key backups are destroyed within 90 days, making a poke completely inaccessible.