Students and faculty from the University of Michigan's Electrical Engineering and Computer Science Department have developed a small device they call ‘HiJack’ to make sensing peripherals easily accessible to those on a small budget. 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 platform enables a new class of small and cheap phone-centric sensor peripherals that support plug-and-play operation. The HiJack communications layer offers two data transfer schemes. The first allows 300 baud data transfer using Bell 202 FSK signaling. The second offers 8.82 kbaud using a Manchester-encoded, direct-digital communication using hardware accelerators on the HiJack microcontroller and a software-defined, digital radio modulator/demodulator on the phone. However as it stands today the group only have four daughterboards, 1: a simple demo board with temperature/humidity sensors, PIR motion sensor, and potentiometer used on the early HiJack prototypes; 2: a 3-lead EKG sensor; 3: a basic soil moisture sensor; 4, a breakout board for fast prototyping on the latest generation of HiJacks. For more information please visit: