Save power usage with security designed FOR the device: This commentary weighs the cost of security (applications and systems) on devices (which may be the rule rather than the exception by the time you read this) in terms of how draining they may be on the battery. The author notes that security implementation requires processing power which demands more of the battery on mobile devices. And that "stupid" security (poorly designed, incompatible, or chucked in as an afterthought) tends to draw off battery power with such mechanisms as polling or anything that keeps the CPU in motion. The author goes on to note that "securing applications by any means" will keep mobile device applications extremely inefficient.
Design on a dime: Power costs for "dumb" security