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A few indoor localization techniques combine inertial sensors with non‐RF signals. In [163], the IDyLL indoor localization system is proposed that combines dead reckoning with light measurements from photodiode sensors on smartphones. Typical luminaire sources (including incandescent, fluorescent, and LED) are often uniquely (sometimes evenly) spaced in many indoor environments. Moreover, most smartphones have light sensors (photodiodes) for automatic brightness adjustment that can theoretically sample at a high rate (e.g. 1.17 MHz for APDS‐9303 on Nexus 5 and 7 devices), although they are often constrained either by the hardware interface or the OS‐level support to a few hertz to up to 100 Hz. IDyLL samples the light sensors at 10 Hz, and uses an illumination peak detection algorithm to gather light readings. The readings are combined with those obtained from inertial sensors, as well as knowledge of the floor map and luminary placement, to achieve fine‐grained indoor localization. The approach in [164] combines dead reckoning, laser scanners, and image‐based localization, all integrated in a human‐carried backpack which can be used to generate 3D models of complex indoor environments. The locations are determined from data capture based on two laser scanners and an inertial measurement unit. The localization performance could be improved by making use of camera images that have been taken in an offline phase. The images can be used to refine the six parameters of the camera pose and improve the quality of the 3D textured model.