Explore a groundbreaking conference talk on ViBand, a technology that transforms smartwatch accelerometers into high-fidelity bio-acoustic sensors. Discover how boosting the sampling rate to 4 kHz unlocks a range of innovative applications, from hand gesture classification to passive object recognition. Learn about the potential for always-available input and interaction through bio-acoustic signals captured by wrist-worn devices. Delve into the custom smartwatch kernel development and its implications for future consumer devices. Examine the possibilities of transmitting data through the human body using structured vibrations. Gain insights into user interface techniques that were previously limited to specialized instrumentation, now made feasible for widespread adoption.