The era of wearables has arrived. As more and more established forms (e.g., a timepiece, a ring, a pendant) get a digital makeover, they are reshaping our everyday experiences with new, useful, exciting and sometimes entertaining services. However, to have a broader impact on our lives, the next generation wearables must expand their monitoring capabilities beyond the narrow set of exercise-related physical activities. To this end, we present eSense an aesthetically pleasing, and ergonomically comfortable in-ear high definition wireless stereo wearable (Figure 1(a)) instrumented with a microphone, a 6-axis inertial measurement unit and dual model Bluetooth and Bluetooth Low Energy (BLE) in an open architecture. These embodiments collectively enable eSense to offer three sensing modalities audio, motion, and proximity derived from microphone, accelerometer, gyroscope, and BLE, respectively. Most importantly, eSense is an entirely open platform that allows developers to gather real-time data streams of these different sensory modalities as well as offering them with several configuration and reprogramming capabilities.