Zac also notes that he doesn’t think that Apple is trying to squash OpenClip on purpose, but it does seem as if Apple is creating a bit of a moving target for developers. Given Apple’s penchant for secrecy, every developer who is trying to write an application that gets relatively deep into the OS has to fear that Apple might just close off some necessary functionality without warning.
That’s an unfair characterization of Apple’s actions and motives. OpenClip worked by exploiting a security hole, and Apple has patched it in 2.1.
Developers aren’t coding against “a moving target”. The whole point of creating and coding against a documented, published, standard API is that the API remains constant while the underlying OS code can change as Apple sees fit during fixes and improvements.
Apps coded against the published APIs have nothing to worry about until there’s a major new release, and in those cases, developers are given ample time to adjust anything that needs it.
OpenClip is trying to hit a moving target because it relies on bad hacks and security exploits to attempt to accomplish something that Apple doesn’t want to be possible (and doesn’t allow).