Embodiments relate generally to electrical and electronic hardware, computer software, wired and wireless network communications, and wearable computing devices for sensing health and wellness-related physiological characteristics. More specifically, disclosed is a physiological sensor using, for example, acoustic signal energy to determine physiological characteristics in one mode, such as a heart rate, the physiological sensor being disposed in a wearable device (or carried device), and generating data communication signals using acoustic signal energy in another mode. The physiological sensor also can be configured to receive data communication signals. In at least one embodiment, an apparatus includes one or more multimodal physiological sensors configured to receive physiological signals in a first mode and at least generate data communication signals in a second mode. A wearable housing includes the multimodal physiological sensors, and a multimodal physiological sensing device is configured to receive a sensor signal and generate data representing a physiological characteristic.
