Device power saving during exercise

1. A smartwatch comprising:

a motion sensor configured to measure a motion;

a positioning unit configured to obtain a location;

an optical heart activity sensor configured to optically measure a heart activity;

a display configured to act as a user interface;

a touch controller configured to make the display touch sensitive;

a wireless interface configured to receive data;

one or more memories including computer program code; and

one or more processing units to execute the computer program code to cause the smartwatch to perform operations comprising:

supporting a normal operating system operation mode during which the smartwatch is configured to run an operating system, control functionality of the display and the touch controller, display notifications regarding incoming calls, messages and social media updates received via the wireless interface, and measure physical activity using data obtained from the motion sensor, data obtained from the positioning unit and data obtained from the optical heart activity sensor;

supporting a limited exercise operation mode during which the smartwatch is configured to control functionality of the display, switch off the touch controller, enable the wireless interface to establish a wireless link with an external physiology exercise sensor, suppress reception of notifications related to incoming calls, messages and social media updates via the wireless interface, and measure physical activity using data obtained from the motion sensor, data obtained from the positioning unit and data obtained from the optical heart activity sensor during a physical activity session performed by a user of the smartwatch; and

switching between the normal operating system operation mode and the limited exercise operation mode.

2. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising

inactivating at least predetermined layers of the operating system when entering the limited exercise operation mode.

3. The smartwatch of claim 1 , wherein a set of functionalities of the smartwatch is available to the smartwatch during the normal operating system operation mode and only a predetermined subset of the functionalities is available to the smartwatch during the limited exercise operation mode.

4. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising:

detecting the beginning of the physical activity session; and

deciding to switch to the limited exercise operation mode at the beginning of the physical activity session.

5. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising:

detecting that the physical activity session is ended; and

entering the normal operating system operation mode.

6. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising:

estimating an ending time of the physical activity session; and

starting to activate the operating system at least a predetermined activation duration before the physical activity session is to be ended, wherein the predetermined activation duration substantially corresponds to the time duration it takes for the operating system to activate.

7. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising:

detecting an exercise profile of the physical activity session;

determining which physical activity-related functionalities are needed during the limited exercise operation mode based on the detected exercise profile; and

running the determined physical activity-related functionalities during the limited exercise operation mode.

8. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising

dynamically limiting the usage of at least one physical activity-related functionality during the limited exercise operation mode.

9. The smartwatch of claim 8 , wherein the smartwatch is further caused to perform operations comprising:

obtaining power consumption information indicating how different physical activity-related functionalities of the smartwatch affect the power consumption rate of the smartwatch;

obtaining functionality usage information indicating which physical activity-related functionalities are typically used during the physical activity session; and

determining the at least one physical activity -related functionality whose usage is to be limited based on the power consumption information and the functionality usage information.

10. The smartwatch of claim 9 , wherein the power consumption information and the functionality usage information are updated after the physical activity session.

11. The smartwatch of claim 8 , wherein the smartwatch is further caused to perform operations comprising:

determining the temperature of the smartwatch and/or an ambient temperature;

obtaining temperature information indicating how temperature affects the power consumption rate of the smartwatch; and

deciding whether or not to dynamically limit the usage based on the determined temperature and the obtained temperature information.

12. The smartwatch of claim 1 , wherein the one or more processing units further comprise:

a low power processing unit configured to run the limited exercise operation mode; and

a high power processing unit configured to run the normal operating system operation mode, wherein the low power processing unit has a lower power consumption in performing a given task than the high power processing unit, and wherein switching to the limited exercise operation mode comprises operations comprising:

activating the low power processing unit; and

inactivating the high power processing unit.

13. The smartwatch of claim 12 , wherein the low power processing unit is a microcontroller unit without a memory management unit, and the high power processing unit is a microprocessor unit with a memory management unit.

14. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising:

running the operating system enabling functionalities of the smartwatch during the normal operating system operation mode; and

running a software separate from the operating system and enabling functionalities of the smartwatch during the limited exercise operation mode.

15. The smartwatch of claim 1 , wherein the operating system comprises a plurality of layers including a library functions-layer and a kernel, and wherein the smartwatch is further caused to perform operations comprising

during the limited exercise operation mode, applying a direct low-level hardware access via hardware drivers of a kernel of the operating system bypassing all other layers of ef—the operating system including the library functions-layer.

16. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising

during the limited exercise operation mode, decreasing a sampling rate of the positioning unit.

17. The smartwatch of claim 1 , wherein the smartwatch is further caused to perform operations comprising

during the normal operating system operation mode, interacting with an external paired mobile phone via the wireless interface.

18. A method; comprising:

supporting a normal operating system operation mode during which an apparatus is running an operating system, controlling functionality of a display and a touch controller, displaying notifications regarding incoming calls, messages and social media updates received via a wireless interface, and measuring physical activity using data obtained from a motion sensor, data obtained from a positioning unit and data obtained from an optical heart activity sensor;

supporting a limited exercise operation mode during which the apparatus is controlling functionality of the display, switching off the touch controller, enabling the wireless interface to establish a wireless link with an external physiology exercise sensor, suppressing reception of notifications related to incoming calls, messages and social media updates via the wireless interface, and measuring physical activity using data obtained from the motion sensor, data obtained from the positioning unit and data obtained from the optical heart activity sensor during a physical activity session performed by a user of the apparatus; and

switching between the normal operating system operation mode and the limited exercise operation mode.

19. A computer program product embodied on a non-transitory distribution medium readable by a computer and comprising computer program code which, when executed by an apparatus, perform a method comprising:

supporting a normal operating system operation mode during which the apparatus is running an operating system, controlling functionality of a display and a touch controller, displaying notifications regarding incoming calls, messages and social media updates received via a wireless interface, and measuring physical activity using data obtained from a motion sensor, data obtained from a positioning unit and data obtained from an optical heart activity sensor;

supporting a limited exercise operation mode during which the apparatus is controlling functionality of the display, switching off the touch controller, enabling the wireless interface to establish a wireless link with an external physiology exercise sensor, suppressing reception of notifications related to incoming calls, messages and social media updates via the wireless interface, and measuring physical activity using data obtained from the motion sensor, data obtained from the positioning unit and data obtained from the optical heart activity sensor during a physical activity session performed by a user of the apparatus; and

switching between the normal operating system operation mode and the limited exercise operation mode.