30. The mobile device of claim 21 wherein the classifier is configured to create the fusion class by selecting the fusion class from a plurality of predetermined available fusion classes.
21. A mobile device comprising: at least one data source comprising one or more sensors of the mobile device; a classifier built into one or more hardware modules of the mobile device, the one or more hardware modules comprising one or more integrated circuits, and communicatively coupled to the at least one data source, wherein the classifier is configured to: receive sensor data from the at least one data source; determine a first context class for the received sensor data, the first context class corresponding to a context state indicated by the received sensor data; determine that a confidence value associated with the determination of the first context class is below a threshold value; create a fusion class for the received sensor data at least in part by fusing the first context class for the received sensor data and at least a second context class for the received sensor data, the at least the second context class being different from the first context class, wherein the fusion class semantically encompasses the first context class and the at least the second context class and further wherein the fusion class is broader than each of the first context class and the at least the second context class; substitute the fusion class for the first context class; and output the fusion class as an inferred context for the mobile device.