Copy Protection Overview

Landscape and Motivation

Applications downloaded from the iTunes App Store are protected by FairPlay DRM. The FairPlay copy protection has been cracked some time ago [1]. What's worse, the copy removal method has been automated by the infamous Crackulous application [2]. The silver lining is that removing the copy protection from applicatins invalidates Apple's signature, so these applications cannot be run on phones without the jailbreak.

iPhone application piracy is significant [3][4][5], so relying on Apple's protection scheme is not a solution for most developers. RIPdev offers a protection scheme that they claim has not been broken so far, but they charge both a setup fee and royalties on an application's sales [6].

Fighting one particular automated process for removing copy protection is easy [7], but curving iPhone application cracking is difficult, because of the many undocumented moving pieces (Apple's signatures, protection mechanism, application approval process, and iTunes distribution). Learning all this is a lot of work, which is currently duplicated by all independent developers who don't want to pay RIPdev. If developers pool their knowledge into the iPhone Wiki, the learning effort will not be duplicated anymore, and applications will have higher overall quality. Ideally, developers will produce an open-source obfuscation mechanism that is trivial to apply to applications, but takes a non-trivial amount of time to reverse.