Update: Like clockwork, it’s out.

Facebook plans to launch its long-awaited Snapchat competitor called Slingshot tomorrow, according to a source. The application briefly became available in some international App Stores last week, and then it (appropriately) swiftly disappeared. The new standalone iPhone application allows users to send a photo or video with text or drawings to another person, but the recipient cannot view it unless they acknowledge that they want to view the message…

An automatic photo reply can also be sent upon viewing the incoming photo or video, according to the briefly available app description from last week. The application, like Facebook’s other apps, will be free on the App Store. This is Facebook’s second attempt at a Snapchat competitor with its failed Poke app appearing in 2012 then disappearing last month. The source warned that Facebook could choose to hold back the launch of Slingshot to a later date if last minute issues surface.