( CNN ) -- Back when Facebook only had millions of users instead of a billion , before Timeline and the bungled IPO and outrage over privacy issues , people `` poked '' each other on the social network . The poke , which is still around but rarely used , is a minimalistic form of communication -- the digital equivalent of a head nod or wink . Now the social network has expanded the poke into a standalone iOS app , which was released on Friday . The simple free app , called Facebook Poke , allows you to send fleeting messages , pokes , photos and 10-second videos to Facebook friends . The messages expire after a set period of time , from 1 to 10 seconds , and can not be retrieved by either party again . This makes the app perfect for sending salacious images without leaving a trail . `` With the Poke app , you can poke or send a message , photo , or video to Facebook friends to share what you 're up to in a lightweight way , '' says Facebook in a blog post announcing the new app . When you open the app , you can choose from a set of icons at the bottom of the screen to send a poke , type a 120-character message , open the camera to snap a picture ( you can not choose an existing photo from your camera roll , but you can add fun doodles or text on top of the picture you do take ) , or shoot a 10-second video . Decide how long you want the other person to see your message or photo ( 1 , 3 , 5 or 10 seconds ) , add a location if you like , then choose one or more of your Facebook friends from the list and hit send . To view a message , tap and hold until the little countdown clock in the corner runs down , and the message is gone forever . You can see a list of who send you messages , but not view them again . The app Poke shamelessly imitates is Snapchat , a photo and video-sharing service that has surged in popularity over the past year year . It 's no mystery why Facebook is jumping on the temporary message bandwagon . Snapchat says it has millions of users who send around 50 million messages a day . It is also popular with the highly valuable younger age group , though it does n't currently have ads or any other way of making money off of its service . The Facebook Poke app is also ad-free for the time being . The allure of self-destructing messages is that they are unlikely to be seen by anyone other than the recipient , or to resurface during a campaign for public office . Snapchat has earned a reputation as a tool for sending risquÃ© photos , though its also handy for funny or silly images for friends . Because of the private nature of these messages , the apps have built-in safeguards . The only way to keep a copy of a photo on these apps is to take a screenshot with your phone . Both Poke and Snapchat warn the sender when the recipient has grabbed a screenshot of their message . Facebook seems keenly aware of how the Poke app will be used by most people . `` If you ever see something you 're uncomfortable with , you can click the gear menu and report it , '' says the company in the post . In the app 's help center there are instructions for what to do when someone takes a screenshot against your will . That section helpfully links to a post on what to do when an adult is making you uncomfortable , and another on what to do when someone requests nude photos . The app is Facebook 's fifth iOS app , joining the main Facebook app , Facebook Messenger and Facebook Camera .
Facebook has released a new , free app for iOS called Facebook Poke . It lets users discreetly send messages , photos and videos that are deleted in a few seconds . The app is available now on the App Store ( http://itunes.apple.com/us/app/poke-for-iphone/ ) Title: Why do we have to wait until after our last meal before