Good God. If true, this is deplorable. As a mobile dev, client-side image caching is one of the easiest things you can do. When an image expires, nuke it off the filesystem.
There are a million and one ways to compromise a local image cache that's intended to be private. You can potentially recover it from the NAND flash if you're sophisticated enough, you can decrypt the data while it's still alive, but deleting the image when you said you would is, well, a pretty basic feature that would prevent the easiest of easy attacks.
I'd expect this sort of thing from an app where people are sending private images, against the initial intent/design. But Snapchat?
There are a million and one ways to compromise a local image cache that's intended to be private. You can potentially recover it from the NAND flash if you're sophisticated enough, you can decrypt the data while it's still alive, but deleting the image when you said you would is, well, a pretty basic feature that would prevent the easiest of easy attacks.
I'd expect this sort of thing from an app where people are sending private images, against the initial intent/design. But Snapchat?