1. A method for controlling behavior tracking by applications executing on a mobile computing device, comprising: managing, by a privacy manager, a set of profiles residing on the mobile computing device, each profile representing a different isolated execution environment on the mobile computing device and defining a set of privacy rules governing an application while executing in the associated execution environment; prompting, by the privacy manager, a user to indicate a profile for a given application by presenting indicia for each of the profiles in the set of profiles, where the prompting occurs prior to and contemporaneous with execution of the given application in an execution environment on the mobile computing device; receiving, by the privacy manager, an input from a user of the given application, the input indicating a profile selected from the set of profiles; and applying, by the privacy manager, the set of privacy rules associated with the selected profile to the given application during execution of the given application, prompting, by the privacy manager, the user to indicate a profile for a second application by presenting indicia for each of the profiles in the set of profiles, where the prompting occurs prior to and contemporaneous with execution of the second application in an execution environment on the mobile computing device; receiving, by the privacy manager, an input from the user of the second application, the input indicating a second profile selected from the set of profiles, where the second profile differs from the first profile; and applying, by the privacy manager, the set of privacy rules associated with the selected second profile to the second application during execution of the given application, where the privacy manager resides on the mobile computing device and is implemented by computer readable instructions executed by a processor of the mobile computing device.