1. A method of observing mobile device behaviors in a mobile device to recognize mobile device behaviors that are benign, the method comprising: monitoring in a processor of the mobile device an activity of a software application or process to collect behavior information; using the collected behavior information to generate a behavior vector information structure that characterizes the monitored activity via a plurality of numbers; determining whether an operating system execution state of the software application or process is relevant to determining whether the monitored activity is benign; generating a shadow feature value that identifies the operating system execution state of the software application or process during which the activity was monitored and including the generated shadow feature value in the generated behavior vector information structure in response to determining that the operating system execution state is relevant to determining whether the monitored activity is benign; and using the generated behavior vector information structure to determine whether the activity is benign.