They vanish once the user responds to them or swipes them away -- a slight distinction from Snapchat messages , which by default disappear after a few seconds . Facebook launches Slingshot , a mobile messaging app for photos , videos . Comment: With Slingshot you ca n't view an incoming message until you respond with your own . Slingshot succeeds Poke , a messaging app that Facebook shut down last month .
Facebook launches Slingshot , a mobile messaging app for photos , videos . Comment: With Slingshot you ca n't view an incoming message until you respond with your own . Slingshot succeeds Poke , a messaging app that Facebook shut down last month .