Abstract: An interactive game environment includes two or more co-located, networked, direction and location aware interactive game devices. The game devices share a common reference coordinate frame (e.g., a three-dimensional Cartesian coordinate frame). Each game device maintains its own device state (e.g., position, orientation, time) in the reference coordinate frame. Each interactive game device shares its device state with the other interactive game devices using communication technology (e.g., Bluetooth, Wi-Fi, cellular). Each interactive game device can use the device states of the other interactive game devices to project the relative positions and orientations of the other interactive game devices into a local, fixed coordinate frame of the interactive game device. These projections allow each interactive gaming device to know the position and orientation of the other interactive game devices in an interactive game environment defined by the reference coordinate frame.

Abstract: Among other disclosed subject matter, a method includes obtaining, in a mobile device, power information indicating a detected power of respective signals received from multiple transmitters. The method includes determining a location of the mobile device using a formula that uses: locations of the multiple transmitters, a first function of the power information and a second function of respective locations of the multiple transmitters. The method can include recording the determined location.

Abstract: A parameter related to the Earth's magnetic field can be used to determine accuracy of a magnetometer of a mobile device. In one aspect, a first instance of a parameter related to Earth's magnetic field is determined using data generated by the magnetometer. The magnetometer data can be based in part on a position of the mobile device with respect to the Earth. A second instance of the parameter can be determined using data generated by a model of Earth's magnetic field. The model data can also be based in part on the position of the mobile device with respect to the Earth. The first instance of the parameter can be compared with the second instance of the parameter. An accuracy metric for the magnetometer can be determined based on a result of the comparison. An indication of the accuracy metric can be presented by the mobile device.

Abstract: Accurate and reliable techniques for determining a current status of an accessory device in relation to an electronic device are described.

Abstract: A parameter related to the Earth's magnetic field can be used to determine accuracy of a magnetometer of a mobile device. In one aspect, a first instance of a parameter related to Earth's magnetic field is determined using data generated by the magnetometer. The magnetometer data can be based in part on a position of the mobile device with respect to the Earth. A second instance of the parameter can be determined using data generated by a model of Earth's magnetic field. The model data can also be based in part on the position of the mobile device with respect to the Earth. The first instance of the parameter can be compared with the second instance of the parameter. An accuracy metric for the magnetometer can be determined based on a result of the comparison. An indication of the accuracy metric can be presented by the mobile device.

Abstract: Systems and methods for activating a mobile device for use with a service provider are described. In one exemplary method, a mobile device having a currently inserted SIM card may be prepared for activation using a signing process in which an activation server generates a signed activation ticket that uniquely corresponds to the combination of the device and SIM card, and that is securely stored on the mobile device. In another exemplary method the mobile device may be activated in an activation process in which the device verifies an activation ticket against information specific to the device and SIM card, and initiates activation when the verification of the activation ticket is successful.

Abstract: A parameter related to the Earth's magnetic field can be used to determine accuracy of a magnetometer of a mobile device. In one aspect, a first instance of a parameter related to Earth's magnetic field is determined using data generated by the magnetometer. The magnetometer data can be based in part on a position of the mobile device with respect to the Earth. A second instance of the parameter can be determined using data generated by a model of Earth's magnetic field. The model data can also be based in part on the position of the mobile device with respect to the Earth. The first instance of the parameter can be compared with the second instance of the parameter. An accuracy metric for the magnetometer can be determined based on a result of the comparison. An indication of the accuracy metric can be presented by the mobile device.

Abstract: A mobile device establishes communication with a number of wireless cellular networks at particular locations and records the locations and network information associated with the wireless cellular networks. The network information can be used to narrow a search for an available wireless cellular network from a plurality of potentially available wireless cellular networks when the mobile device is operating at a stored location. In one aspect, a Radio Frequency (RF) receiver on a mobile device can receive a broadcast radio signal from a transmitter and use the signal to determine an approximate location of the device based on a known location of the transmitter. A match between the approximate device location and wireless cellular network transmitters in communication range of the mobile device can be used to narrow a search for wireless cellular networks.

Abstract: Systems and methods for activating a mobile device for use with a service provider are described. In one exemplary method, a mobile device having a currently inserted SIM card may be prepared for activation using a signing process in which an activation server generates a signed activation ticket that uniquely corresponds to the combination of the device and SIM card, and that is securely stored on the mobile device. In another exemplary method the mobile device may be activated in an activation process in which the device verifies an activation ticket against information specific to the device and SIM card, and initiates activation when the verification of the activation ticket is successful.

Abstract: Techniques for performing more accurate snap-to-road calculations using wireless access point data are disclosed. In one aspect, a corrected location corresponding to received location data is selected from a plurality of candidate map locations based on a correspondence between the access points visible to a device and the access points visible at the corrected map location. In another aspect, road vector data is augmented with access point data, and a corrected map location is selected based on a correspondence between the access points visible to the device, and the augmented road vector data.

Abstract: A location aware device includes a navigation system and one or more environment sensors. Sensor output(s) are aggregated and used to determine a context for the location aware device. Based on the determined context, context data is generated and provided to a navigation engine where it can be used to determine a navigation solution.

Abstract: A location aware mobile device can include a baseband processor for communicating with one or more communication networks, such as a cellular network or WiFi network. In some implementations, the baseband processor can collect network information (e.g., transmitter IDs) over time. Upon request by a user or application, the network information can be translated to estimated position coordinates (e.g., latitude, longitude, altitude) of the location aware device for display on a map view or for other purposes. A user or application can query the location history database with a timestamp or other query to retrieve all or part of the location history for display in a map view.

Abstract: A parameter related to the Earth's magnetic field can be used to determine accuracy of a magnetometer of a mobile device. In one aspect, a first instance of a parameter related to Earth's magnetic field is determined using data generated by the magnetometer. The magnetometer data can be based in part on a position of the mobile device with respect to the Earth. A second instance of the parameter can be determined using data generated by a model of Earth's magnetic field. The model data can also be based in part on the position of the mobile device with respect to the Earth. The first instance of the parameter can be compared with the second instance of the parameter. An accuracy metric for the magnetometer can be determined based on a result of the comparison. An indication of the accuracy metric can be presented by the mobile device.

Abstract: A parameter related to the Earth's magnetic field can be used to determine accuracy of a magnetometer of a mobile device. In one aspect, a first instance of a parameter related to Earth's magnetic field is determined using data generated by the magnetometer. The magnetometer data can be based in part on a position of the mobile device with respect to the Earth. A second instance of the parameter can be determined using data generated by a model of Earth's magnetic field. The model data can also be based in part on the position of the mobile device with respect to the Earth. The first instance of the parameter can be compared with the second instance of the parameter. An accuracy metric for the magnetometer can be determined based on a result of the comparison. An indication of the accuracy metric can be presented by the mobile device.

Abstract: Automatically identifying a geographic direction (e.g., a heading relative to true north) is disclosed. Responsive to a correction trigger event, geographic position data that identifies a geographic position of the device can be obtained. A magnetic declination based on the geographic position data can be obtained. A magnetic heading of the device can be obtained. A geographic direction based on the magnetic heading and the magnetic declination can be identified without user intervention.

Abstract: Responsive to a recalibration trigger event, magnetometer data output by a magnetometer can be compared to historical magnetometer data previously output by the magnetometer. If a match is determined, a confidence of the match can be determined using theoretically constant data related to Earth's magnetic field. The constant data can be calculated from the historical magnetometer data. If the confidence of the match exceeds a confidence threshold level, historical calibration data can be used to calibrate the magnetometer. If the confidence of the match does not exceed the confidence threshold level, a calibration procedure can be performed to generate new calibration data, and the new calibration data can be used to calibrate the magnetometer.

Abstract: Customizing a device based on space and time (e.g., a geographic position of the device at a particular time) is disclosed. In one aspect, geographic position data of a device is obtained. Temporal data that is related to the geographic position data is obtained. An operational mode is selected based on the geographic position data and the temporal data for activation on the device. In some implementations, the operational mode identifies a communication medium.

Abstract: An interactive game environment includes two or more co-located, networked, direction and location aware interactive game devices. The game devices share a common reference coordinate frame (e.g., a three-dimensional Cartesian coordinate frame). Each game device maintains its own device state (e.g., position, orientation, time) in the reference coordinate frame. Each interactive game device shares its device state with the other interactive game devices using communication technology (e.g., Bluetooth, Wi-Fi, cellular). Each interactive game device can use the device states of the other interactive game devices to project the relative positions and orientations of the other interactive game devices into a local, fixed coordinate frame of the interactive game device. These projections allow each interactive gaming device to know the position and orientation of the other interactive game devices in an interactive game environment defined by the reference coordinate frame.

Abstract: Location data is exchanged between a portable media device and an accessory. If the portable media player is equipped with location determining capability, the portable media device can communicate its location data to the accessory, and the accessory can use this location data to perform various tasks. If the accessory is equipped with location assistance capability, the accessory can communicate location data to the portable media device, and the portable media device can use this location data to perform various tasks.

Abstract: A number of devices co-located at a geographic location can broadcast and receive tokens. Tokens can be exchanged using a communication link having limited communication range. Tokens that are received by a device can be stored locally on the device and/or transmitted to a trusted service operating remotely on a network. In some implementations, the tokens can be stored with corresponding timestamps to assist a trusted service in matching or otherwise correlating the tokens with other tokens provided by other devices. The trusted service can perform an analysis on the tokens and timestamps to identify devices that were co-located at the geographic location at or around a contact time which can be defined by the timestamps. A group can be created based on results of the analysis. Users can be identified as members of the group and invited to join the group.