Cell phones and other portable devices are equipped with a variety of technologies by which existing functionality can be improved, and new functionality can be provided. Some relate to visual search capabilities, and responding to different image inputs and different contexts. Others relate to processing of image data. Still others concern metadata generation, processing, and representation. Yet others relate to coping with fixed focus limitations of cell phone cameras, e.g., in reading digital watermark data. Still others concern user interface improvements. Yet others concern adapting behavior of a camera-equipped system based on previously-captured imagery. A great number of other features and arrangements are also detailed.