1. A device comprising: a camera configured to capture an image, wherein the image includes a digital representation of a respondent's physical response device bearing a symbol, and wherein the symbol specifies the respondent's response to a poll and an identifier of the respondent; a processor communicatively coupled to the camera and configured to analyze the captured image to decode the symbol and to determine the respondent's identifier and response to the poll; and a storage device communicatively coupled to the processor and configured to store the determined response.