On: Snaprecovery: Recover old Snaps that have “disappeared” from Snapchat

[pessimizer]

The person you're replying to is referring to making the files unrecoverable. The word most often used is "shred."

edit: The Snapchat app, like the vast majority of applications, asks the OS to delete files. It very probably doesn't have any direct access to I/O.

[treesknees → pessimizer]

Seems like an API that the OS should expose. I'm sure other apps like banking/financial would benefit from this, too.