This Product has been discontinued.
HiJack is a hardware/software platform for creating cubic-inch sensor peripherals for the mobile phone. HiJack devices harvest power and use bandwidth from the mobile phone's headset interface. The HiJack platform enables a new class of small and cheap phone-centric sensor peripherals that support plug-and-play operation. HiJack has been tested with the iPhone 3G/3GS/4G, iPod Touch, and iPad devices.
Or check out the transparent article, HiJack and techBASIC “Hello world!” Project, from Mike Westfield.