Abstract: A personal mobile device housing contains a display screen, a wireless telephony communications transceiver, and a battery charger interface. A temperature sensor and a gyro sensor whose zero turn rate output contains an offset are also included. A lookup table has gyro zero turn rate offset correction values associated with different temperature values. A programmed processor accesses the lookup table to correct the output of the gyro sensor for zero turn rate offset. It is automatically determined, during in-the-field use, when the device is in a motionless state, and the output of the temperature and gyro sensors are read. The read gyro output is written to the lookup table as part of a pair of associated temperature and zero turn rate offset correction values. Other embodiments are also described and claimed.

Abstract: An electronic device such as a portable music player, cellular telephone, or computer may be provided with an audio jack system that allows audio plug position measurements to be made. Sensors such as optical sensors, magnetic sensors, mechanical sensors, electrical sensors, resistive sensors, and capacitive sensors may be used in monitoring the position and movement of the audio plug relative to the audio jack. A user may rotate the audio plug to control operations such as media playback operations, menu selection operations, and other activities in the electronic device. The audio jack may include flexible structures that allow the audio plug to be tilted relative to the audio jack. Capacitive sensors or other sensors may be used to monitor audio plug tilt and axial audio plug movement. This allows the audio plug to serve as a joystick for the electronic 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: 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 compass output in a first portable electronic device is monitored as the first device and a second electronic device come closer to each other. It is determined, by a process running in the first device, whether a magnetic field signature that is based on the monitored compass output is associated with a previously defined type of electronic device with which a network device discovery process is to be conducted. Other embodiments are also described and claimed.

Abstract: Multiple instances of a geomagnetic field are calculated. Multiple instances of an average magnitude of a subset of the instances of the geomagnetic field are also calculated. When the average magnitude changes by more than a first predetermined threshold, the user is informed that compass accuracy has degraded. Other embodiments are also described and claimed.

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: Multiple instances of a geomagnetic field are calculated. Multiple instances of an average magnitude of a subset of the instances of the geomagnetic field are also calculated. When the average magnitude changes by more than a first predetermined threshold, the user is informed that compass accuracy has degraded. Other embodiments are also described and claimed.

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: Measurement data is collected from a magnetic sensor in a portable device, while the device is being carried by its end user and without requiring the end user to deliberately rotate or position the device while the output data is being collected. For example, the device may be held in the user's hand while walking or standing, or it may be fixed to the dashboard of an automobile or boat. Measurement data may also be collected from one or more positing, orientation or movement sensors. The collected measurement data from one or both of the magnetic sensor and the position, orientation or movement sensor is processed. In response, either a 2D compass calibration process or a 3D process is signaled to be performed. Other embodiments are also described and claimed.

Abstract: A controller detects the temperature of a portable electronic device as being below a battery charging threshold, and in response signals one or more of the electronic circuit components that make up the device to enter an increased power consumption state so as to generate more heat in the device for warming up the battery. Other embodiments are also described and claimed.

Abstract: A device to capture an image includes a camera oriented to capture a first image of a subject and a display oriented to display a second image that is viewable by the subject. A backlight is coupled to the display to provide light that passes through the display toward the subject. An image processor is coupled to the camera and the backlight to adjust an amount of light provided by the backlight responsive to a quality of the first image. The light provided by the backlight may illuminate the subject and thereby improve the quality of the first image. The image processor may further adjust the amount of light provided by the backlight responsive to an ambient light level sensed by an ambient light sensor. The image processor may further adjust the second image to adjust an amount of light that passes through the display.