But doesn't client-side encryption already function at the OS level? For instance, the keys for FairPlay and the App Store have not been cracked, as far as I know.
FairPlay has been cracked a lot of times, there have been many tools to remove the DRM from FairPlay encrypted songs/videos/books.
App store apps have also been cracked in that their keys have been stripped, on a jail broken phone you can run all those apps without needing a valid key.
FairPlay video was (kind of) cracked a few years ago I was in the habit of decrypting TV episodes using Requiem so I could watch them on my Linux netbook. You had to decrypt the files on a computer with iTunes installed though.
I don't know if Requiem has been keeping up with the latest iTunes releases.
