An innovative accessory for the iPhone 3G or 3GS has been created that is an external battery with built-in adapter for the second SIM card.
The device will charge your iPhone and it will also let you swap between SIM cards with ease via an application installed on the phone. For a businessman who owns an iPhone 3G or 3GS and frequently needs to switch between two cellular networks, this accessory works best for your iPhone. For example, to switch phone numbers when traveling between countries, It will give iPhone users more convenience. The device is available right away for just $60
