A computer-implemented method is provided for reducing power consumption of a power source used by a mobile device. The mobile device monitors aspects of its environment to determine if some or all of the device's computing functionality can be handled seamlessly by another nearby device. For example, phone calls can be directed to a landline phone nearby the mobile device. A device usage policy defines how certain functions are to be handled by the mobile device, for example, at a given location or amongst two devices. The mobile device can then disable functionality that is being handled by nearby devices, thereby reducing power consumption by the mobile device.