Abstract: Immersive audio can be generated and/or updated in real-time as an accessory device presenting the audio is moved with respect to a computing device presenting accompanying video content. This real-time immersive audio is enabled by determining positions of the accessory device with respect to the computing device, based on real-time analysis of sensor information from the accessory device and the computing device. Accurate positions can be determined by synchronizing timestamped sensor data from the multiple devices through the use of a clock of a common wireless communication link (e.g., a Bluetooth connection), which may have lower drift than the global clocks of the devices themselves. Calculated offsets associated with differences between the clock of the wireless communication link and the global clocks of the multiple devices can be used to account for inaccuracies in the global clocks of the multiple devices with respect to one another.

Abstract: In general, in one aspect, a method includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, determining, based on data received from a location system of the mobile device, that the mobile device has remained within a geographic area during a time interval, the geographic area being defined by a radius determined according to an application type of the application, and disabling at least a portion of the location system of the mobile device.

Abstract: Systems, methods, and program products for determining a location of a mobile device using a location application programming interface (API) are described. A mobile device can receive an input requesting the mobile device to monitor entry into and exit from a significant location. The mobile device can call a start-monitoring instance function of an object of a location manager class as declared in the API to start monitoring, and call a stop-monitoring instance function of the object as declared in the API to stop monitoring. The mobile device can store the entry and exit, or provide a record of the entry or exit to a function that is conformant to the API for performing various tasks.

Abstract: Systems, methods, and program products for determining a location of a mobile device using a location application programming interface (API) are described. A mobile device can receive an input requesting the mobile device to monitor entry into and exit from a significant location. The mobile device can call a start-monitoring instance function of an object of a location manager class as declared in the API to start monitoring, and call a stop-monitoring instance function of the object as declared in the API to stop monitoring. The mobile device can store the entry and exit, or provide a record of the entry or exit to a function that is conformant to the API for performing various tasks.

Abstract: Using various functionalities of electronic devices such as applications that gather location information to provide a service to the user can come at the cost of significant power consumption, and consequently battery drainage. A data sharing system enables the creation of a network of participant devices where participant devices in the network can take turns in collecting and sharing data with the rest of the participant devices in the network. The one or more participant devices can share the obtained data through Bluetooth® low energy (BTLE) or other low consumption channel, so that the ensemble of participant devices could have better battery life, higher availability, and/or better accuracy, compared to each device having to individually obtain the data.

Abstract: Methods for operating portable electronic devices to maintain accurate timing information are provided. In one suitable arrangement, an electronic device may have a real-time clock and a mach-time clock that can be used separately to track the Coordinated Universal Time (UTC). The offset of the real-time clock and the mach-time clock from UTC can be monitored to determine if there is any oscillator frequency drift, which can be characterized using a linear model. Any variation in drift caused by environment factors such as temperature may also be characterized. In another suitable arrangement, a primary electronic device that is capable of maintaining accurate timing information may transfer that information to a secondary user device. Timing information may be transferred using mach-time values and may then be converted to real-time clock values to ensure that the secondary user device can estimate time accurately even when the device goes to sleep.

Abstract: In general, in one aspect, a method includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, determining, based on data received from a location system of the mobile device, that the mobile device has remained within a geographic area during a time interval, the geographic area being defined by a radius determined according to an application type of the application, and disabling at least a portion of the location system of the mobile device.

Abstract: In general, in one aspect, a method includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, determining, based on data received from a location system of the mobile device, that the mobile device has remained within a geographic area during a time interval, the geographic area being defined by a radius determined according to an application type of the application, and disabling at least a portion of the location system of the mobile device.

Abstract: Methods for operating portable electronic devices to maintain accurate timing information are provided. In one suitable arrangement, an electronic device may have a real-time clock and a mach-time clock that can be used separately to track the Coordinated Universal Time (UTC). The offset of the real-time clock and the mach-time clock from UTC can be monitored to determine if there is any oscillator frequency drift, which can be characterized using a linear model. Any variation in drift caused by environment factors such as temperature may also be characterized. In another suitable arrangement, a primary electronic device that is capable of maintaining accurate timing information may transfer that information to a secondary user device. Timing information may be transferred using mach-time values and may then be converted to real-time clock values to ensure that the secondary user device can estimate time accurately even when the device goes to sleep.

Abstract: Systems, methods, and program products for determining a location of a mobile device using a location application programming interface (API) are described. A mobile device can receive an input requesting the mobile device to monitor entry into and exit from a significant location. The mobile device can call a start-monitoring instance function of an object of a location manager class as declared in the API to start monitoring, and call a stop-monitoring instance function of the object as declared in the API to stop monitoring. The mobile device can store the entry and exit, or provide a record of the entry or exit to a function that is conformant to the API for performing various tasks.

Abstract: A method for using a location to refine network-provided time zone information is disclosed. The method can include a wireless communication device receiving a time zone information message from a network; determining multiple candidate time zones matching a set of time zone identification parameters included in the received time zone information message; deriving a location of the wireless communication device; and using the location to select a current time zone for the wireless communication device from the candidate time zones matching the set of time zone identification parameters.

Abstract: Systems and methods are provided for configuring settings of a mobile device based on an inferred location. The mobile device can use stored indicia of trip (e.g., an electronic ticket or itinerary) to identify origination and destination locations. The start and end of the trip can be inferred based on changes in operation of the mobile device. For instance, if the user is on an airplane, the user may turn off network connectivity at the origination location just prior to takeoff, and may turn the network connectivity back on upon landing at the destination location. If the time that elapsed between the changes in operation is consistent with the duration of the trip indicated by the stored indicia, the mobile device can infer that the current location is the destination location. The mobile device can then configure location-specific settings in accordance with the destination location to establish a network connection.

Abstract: Among other things, we describe a method that includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, receiving, from the application, a value indicating a condition for providing location data to the application, disabling a resource associated with the application, while the resource associated with the application is disabled, storing location data received from a location system of the mobile device, and when the condition indicated by the value is met, enabling the resource associated with the application, and providing the stored location data to the application.

Abstract: Systems and methods are provided for configuring settings of a mobile device based on an inferred location. The mobile device can use stored indicia of trip (e.g., an electronic ticket or itinerary) to identify origination and destination locations. The start and end of the trip can be inferred based on changes in operation of the mobile device. For instance, if the user is on an airplane, the user may turn off network connectivity at the origination location just prior to takeoff, and may turn the network connectivity back on upon landing at the destination location. If the time that elapsed between the changes in operation is consistent with the duration of the trip indicated by the stored indicia, the mobile device can infer that the current location is the destination location. The mobile device can then configure location-specific settings in accordance with the destination location to establish a network connection.

Abstract: Using various functionalities of electronic devices such as applications that gather location information to provide a service to the user can come at the cost of significant power consumption, and consequently battery drainage. A data sharing system enables the creation of a network of participant devices where participant devices in the network can take turns in collecting and sharing data with the rest of the participant devices in the network. The one or more participant devices can share the obtained data through Bluetooth® low energy (BTLE) or other low consumption channel, so that the ensemble of participant devices could have better battery life, higher availability, and/or better accuracy, compared to each device having to individually obtain the data.

Abstract: Among other things, we describe a method that includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, receiving, from the application, a value indicating a condition for providing location data to the application, disabling a resource associated with the application, while the resource associated with the application is disabled, storing location data received from a location system of the mobile device, and when the condition indicated by the value is met, enabling the resource associated with the application, and providing the stored location data to the application.

Abstract: A method for using a location to refine network-provided time zone information is disclosed. The method can include a wireless communication device receiving a time zone information message from a network; determining multiple candidate time zones matching a set of time zone identification parameters included in the received time zone information message; deriving a location of the wireless communication device; and using the location to select a current time zone for the wireless communication device from the candidate time zones matching the set of time zone identification parameters.

Abstract: Among other things, we describe a method that includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, receiving, from the application, a value indicating a condition for providing location data to the application, disabling a resource associated with the application, while the resource associated with the application is disabled, storing location data received from a location system of the mobile device, and when the condition indicated by the value is met, enabling the resource associated with the application, and providing the stored location data to the application.

Abstract: In general, in one aspect, a method includes receiving, on a mobile device, an indication that an application executing on the mobile device has entered a background state, determining, based on data received from a location system of the mobile device, that the mobile device has remained within a geographic area during a time interval, the geographic area being defined by a radius determined according to an application type of the application, and disabling at least a portion of the location system of the mobile device.