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There are a few other signals that can aid with indoor localization. Atmospheric pressure can be captured using barometric/altitude/pressure sensors, and used to provide estimates of the altitude of the person or object to be tracked. Magnetic readings captured by a (digital) compass can also be used for heading (direction) estimation. Most IMUs today include three perpendicular magnetometer sensors to measure the strength and/or direction of a magnetic field, along with traditional 3‐axis accelerometer sensors for motion estimation, and 3‐axis gyroscope sensors to measure angular rotation. However, spurious electromagnetic field disturbances can affect the readings of the magnetometer sensors when in proximity to metallic structures or radio‐wave‐emitting devices.

In general, the signals discussed above can help improve the accuracy of indoor localization when used in tandem with other more robust and comprehensive localization signals, for example, dead reckoning or RF‐signal‐based localization.