Patent attributes
Methods, systems, and apparatus, including computer programs encoded on computer storage media, for audience measurement using a mobile device accessory are disclosed. In one aspect, a mobile device accessory includes a power source configured to provide power to the mobile device. The mobile device accessory further includes an audio capturing device configured to capture an ambient sound, and a microprocessor coupled to the audio capturing device and configured to identify distinctive features of the ambient sound and generate a digital representation of the ambient sound. The mobile device accessory further includes a memory coupled to the microprocessor and configured to store at least the digital representation, and a transmitter coupled to the microprocessor and configured to transmit at least the digital representation.
