Vooma has announced an iPhone case with a backup battery and, more interestingly, an unlocked SIM slot. The case works with a jailbreak-only app that emulates the iPhone's native phone app to allow calls via the external SIM. At its core, the case unlocks any jailbroken iPhone.
TechCrunch's John Biggs tried a pre-release version of the case and came away impressed:
Once it’s set up the Peel PG92 works seamlessly and even uses a similar interface to Apple’s own dialer – although it’s clear that the programmers had to cut a few corners to get the look and feel correct. For example, the dialing screen is actually a bitmapped copy of the original dialer and the letters and numbers are slightly warped. However, all of the major functionality is recreated in the Vooma app.
However, this is clearly a very cool and clever hack and it works without problems on any jailbroken iPhone.
Details are scarce, but it appears that the case fits mini-SIM cards, not the micro-SIM that fits in the iPhone 4 and 4S. Also, the external SIM could be used for voice calls only -- data most likely goes through the SIM card that's installed in the iPhone. Because the external SIM is used via its own app the internal SIM can still be used for voice calls even with the case installed.
The case would be most useful for international travelers who wish to install a prepaid SIM card from a local carrier, without having to unlock their subsidized iPhone from a domestic carrier. Unlocking an iPhone is typically more difficult than a simple jailbreak.
Vooma has a sign-up form on its homepage to get more information on the Peel PG920, but the company has disclosed no details about pricing or availability.
