1. A wireless end-user device, comprising: a wireless modem to communicate data for network service usage activities between the device and a wireless network; a processor that executes instructions to associate network service usage activity, on behalf of a first device application, and that occurs when the first device application is not in the foreground of user interaction, with a network service usage control policy, set an application state indicating whether the first device application, associated with a particular network service usage activity, is in the foreground of user interaction, and dynamically determine whether to apply the network service usage control policy to the particular network service usage activity, based on the application state and based on a power control state; and a memory coupled to the processor to provide the processor with the instructions.