Location tracking is not just about triggering advertising avalanches when you pass a store. Location is an important element in a field of artificial intelligence called contextual awareness. It can be used for determining where you are and where you're going, as well as your current needs. It is normal to expect a person will behave differently in church than in discos.
Context-awareness refers to giving devices the intelligence to distinguish between a sacrament and a party and adapt accordingly. To get more details about underground tracking you may browse this site.
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Traditional activity detection
Mobile phones can detect activity using location data and accelerometer data. Local radio towers and wi-fi signals can be used to calculate location estimates. Or, you can use GPS directly. The accelerometer can also be used to determine the location of a person. The frequency of periodic movements is specific to certain activities, such as running, cycling, and walking. A person can track her progress and determine when she walks or runs by using the peak of the accelerometer signal.
The problem of inferring user activity from their location and accelerometer data was thoroughly researched. It is simple to determine if a user is running, walking, or biking. The accelerometer is not useful for detecting automobile transportation such as driving a car or riding a bus or train.
Although you would expect that vehicle accelerations would leave a trace on your phone's accelerometer data it is actually very weak. This is where location can be used to calculate features such as average speed, maximum speed, frequency, and location of stops. These can be compared to nearby roads, intersections, rails, or bus stops. Again, these are excellent performances.