A smart phone senses audio, imagery, and/or other stimulus from a user's environment, and acts autonomously to fulfill inferred or anticipated user desires. In one aspect, the detailed technology concerns phone-based cognition of a scene viewed by the phone's camera. Recognition tasks, selected with the aid of context, are allocated increased or decreased resources based on data comprising (a) user input data indicating express or implied encouragement or discouragement of the recognition task and/or (b) a detection state metric, representing a quantified likelihood that the recognition goal sought by the recognition task will be reached. A great number of other features and arrangements are also detailed.