Always faddish in their production of knock-offs and crap gadgets, the black market electronic shops of the Far East have lately been disgorging a surplus of cases that sandwich in a SIM slot and a cellular radio, thus allowing you to make phone calls on your jailbroken iPod Touch. They’re clever hacks, to be sure, but it appears that Cupertino itself has already thought of just that approach to transforming an iPod Touch into an iPhone… and if Apple can think of it, you can bet that they’ve patented it.

In fact, earlier this year, Apple filed a patent application for an “accessory transceiver” that would bring mobile calling and data to the iPod Touch. You know, just like the Peel 520. Or the tPhone. Or any of the other iTouch-to-iPhone cases we’ve written about since August.

The difference here is that Apple doesn’t actually seem to be aiming this patent specifically at bringing telephone capabilities to the Touch as an accessory. Rather, the patent filing talks about this as possible strategy for bringing CDMA compatibility to the iPhone.

Obviously, either approach — whether transforming the iPod Touch into an iPhone, or adding CDMA onto the iPhone through a case — is too much of a kludge for Apple to seriously consider. My guess is that these patent filings are a blocking maneuver in case another company did try to use a case to graft new capabilities onto existing iOS devices: by controlling the patents, Apple can block the tech… and therefore any competitors that might want to use third-party cases to piggyback off of Apple’s success in unauthorized ways.

[via Engadget]