Apple buys Silicon Valley startup WiFiSlam to acquire indoor WiFi geolocation technology

March 26, 2013 // By Julien Happich
Apple has acquired a Silicon Valley startup, WiFiSlam, which makes mapping applications for smart phones based on the triangulation of WiFi signals. The Wall Street Journal reported Apple may have paid around $20 million for the company.

WiFiSlam develops technology that provides indoor tracking and similar services. Big tech companies such as Apple and Google have been racing to provide more and better map applications for users. Google's application, Google Maps, is widely accessed on Google's Android platform and rival Apple's rival iOS platform.

The startup uses a combination of methods to get better indoor locations, such as using WiFi fingerprinting, or measuring the strength of the signal to get an idea of what the materials and construction of a particular building do to WiFi signals. With enough scans, users can get an accurate profile of a building that can be then be used to make a map. Slam stands for Simultaneous Localization and Mapping, at the core of WiFiSlam's way of gathering location and mapping information, without recording any data at all. WiFiSlam records 'trajectories’ from the phone’s sensors including the accelerometers, gyroscopes and magnetometers and combine them with WiFi signal strength data.

By aggregating the data of many paths walked by various users, a big database of paths and maps can be built for each building equipped with WiFi hotspots. Pattern recognition and machine learning algorithms are also blended-in to correlate the data gathered by all of the sensors in a device, and associate it with WiFi triangulation. Magnetometers can take magnetic field readings throughout a building, and again, the level of variance and details provided can be used to statistically map indoor locations together with the WiFi signals. All these sensors are already on-board Apple’s iPhone 5 and iPhone 4S. This could turn any iPhone user into a remote anonymous data aggregator, adding precision to future Apple indoor mapping services.