Immi have developed a innovative piece of technology that turns a cellphone into a media surveying device. The IMMI^(SM) phone randomly samples 10 seconds of room audio every 30 seconds. These samples are reduced to digital signatures, which are uploaded continuously to the IMMI servers. IMMI also tracks all local media outlets actively broadcasting in any given designated media area (DMA). To identify media, IMMI^(SM) compares the uploaded audio signatures computed by the phones with audio signatures computed on the IMMI servers monitoring TV and radio broadcasts. IMMI also maintains client-provided content files, such as commercials, promos, movies, and songs. By matching the signatures, IMMI couples media broadcasts with the individuals who are exposed to them. The process takes just a few seconds.

The system relies on audible media so does not pick up for instance a television on mute. Yet the technology is still pretty impressive (if it works). To date most media companies have been reliant on diaries completed by panel members or set top boxes, something that IMMI may be able to send into retirement.