Abstract: A method for calculating a representation of energy expenditure, according to one embodiment, includes receiving input from multiple source, the sources including at least one sensor. An energy expenditure value is calculated based on the input. A method for utilizing real-time sensor data to guide breathing, according to one embodiment, includes receiving biometric sensor data about a user wearing a wearable device. An output is selected based on the sensor data for guiding a breathing rate and/or a breathing depth of the user. The selected output is sent to an output subsystem selected from the group consisting of an output subsystem of the wearable device and an output subsystem of a host. A different output is selected in response to detecting a change in the biometric sensor data.

Abstract: A method for predictively controlling an operational state of a wearable device, according to one embodiment, includes collecting historical sensor data acquired by one or more sensors of a wearable device. The historical sensor data is analyzed for detecting a pattern therein. A time to change an operational state of the wearable device is predicted based on the analysis. The change of the operational state is instructed at the predicted time.

Abstract: A wearable device having sensor-dependent behavior modification, according to one embodiment, includes a housing configured for positioning on a human body. A plurality of sensors are positioned in and/or on the housing for detecting a condition of the wearable device and/or an environment of the wearable device. A processing circuit in the housing is coupled to the sensors for receiving sensor data therefrom. A computer readable storage medium is coupled to the processing circuit, the computer readable storage medium having program instructions stored therein, which when executed by the processing circuit cause the processing circuit to change a state of the wearable device based on the sensor data.