1. A method of adaptively controlling operation of a portable computing system based on computing system context, the portable computing system including a processor, an imaging sensor system that outputs frames of image information, and audio sensor system that outputs audio information, the method comprising the acts: for a first interval, in which the processor has a first utilization, applying an image recognition operation to all of plural frames of image information output by the imaging sensor system; for a second interval, in which the processor has a second utilization higher than the first utilization, and during which the imaging sensor system outputs N frames of image information, applying said image recognition operation to M of said frames, where 0<M<N; for a third interval, in which the processor has a third utilization, applying an audio recognition operation to all of the audio information output from the audio sensor system; and for a fourth interval, in which the processor has a fourth utilization higher than the third utilization, applying said audio recognition operation to none of the audio information output from the audio sensor system; wherein the image recognition applied to frames of image information output by the imaging sensor system is throttled-back with an increase in processor utilization, whereas the audio recognition applied to audio information output by the audio sensor system is discontinued with an increase in processor utilization.