Fitness-tracking smartphone apps, smartwatches, and bands need continuous location data for mapping and recording, and accuracy is critical for wearers who like to monitor their progress and share achievements online. A built-in eCompass helps calculate location when satellite signals are unavailable, such as inside buildings or when running or cycling under tree cover. A new eCompass reduces the heading error to less than 4° instead of the typical 10° of current devices.

The STMicroelectronics (ST) LSM303AGR eCompass combines a 3-axis MEMS accelerometer and a very compact 3-axis Anisotropic Magneto-Resistive (AMR) sensor on a single die. The AMR sensor delivers not only higher sensitivity and lower noise than conventional Hall sensors is has also temperature stability compared to alternatives made using Giant Magneto-Resistive (GMR) or Tunnel Magneto-Resistive (TMR) technology. The AMR sensor also has high dynamic range, which further contributes to the device's accuracy by preventing magnetic saturation in areas of high ambient-field strength.

According to the manufacturer, the eCompass has been tested at various latitudes and recorded superior accuracy and temperature stability over similar ICs and pure magnetic sensors from competing manufacturers.