1. A method for using position information about a mobile device to enhance user experience, the method comprising: detecting, by a processor, a motion mode of the mobile device based on data collected from one or more sensors coupled to the mobile device; detecting, by the processor, a location of the mobile device on a user's body based on the detected motion mode and on the collected sensor data; and providing situational awareness information to the user based on the detected motion mode and the detected location of the mobile device, wherein detecting the motion mode of the mobile device includes: obtaining frequency-domain spectral information from the collected sensor data; comparing the spectral information from the collected sensor data to spectral information in two or more sets of training data, each set of training data in the two or more sets of training data corresponding to one of a plurality of particular motion modes; and determining, based on the comparison, the motion mode of the mobile device.