The iPhone 4 can do plenty, even play nicely on other GSM networks when you’ve unlocked it with ultrasn0w, but up until now you couldn’t put two SIM cards inside it.  I-smartsim’s new iPhone 4 Dual SIM Adapter Case doesn’t quite change that – the two SIMs in question aren’t exactly within the iPhone – but it does allow you to easily flip between cards without reaching for the Liquidmetal tool.

 That’s because each SIM clips into a special adapter that then snakes round the side of the iPhone 4 and into the regular SIM tray.  A transparent plastic shell keeps everything safely in place, and there’s no need to cut the cards beforehand.

Now, you can’t have both SIMs active at the same time – that’s a limitation of the iPhone 4, sadly – but you can apparently switch between them without having to reboot the Apple smartphone.  According to I-smartsim, you can simply pick the correct card from the SIM Applications menu in the iPhone 4′s settings, and after a minute or two it flicks over.  You’ll need to be running iOS 4.0.0/4.0.1/4.0.2 for that to work, though

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Three SIM CARD

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