They are implemented in the existing chips just not enabled in software. Qualcomm's ubiquitous LTE modem chip has FM radio baked in. There was a whole push by t

They are implemented in the existing chips just not enabled in software. Qualcomm's ubiquitous LTE modem chip has FM radio baked in. There was a whole push by the FCC in the US as well as some FM broadcasters to mandate it be enabled. See: "Your Phone Has An FM Chip. So Why can't you listen to the radio?": https://archive.is/YMLsM#selection-1393.0-1393.64 https://archive.is/YMLsM#selection-1393.0-1393.64 and "Dinosaur Broadcasters Turn to Congress to Mandate Their Relevance": https://www.forbes.com/sites/garyshapiro/2012/06/06/dinosaur-broadcasters-turn-to-congress-to-mandate-their-relevance-2/?sh=6a687989422a https://www.forbes.com/sites/garyshapiro/2012/06/06/dinosaur... and "Trump’s FCC chief wants it to be easier to listen to free FM radio on your smartphone": https://www.vox.com/2017/2/16/14638304/trump-fcc-free-fm-radio-chip-smartphone-pai https://www.vox.com/2017/2/16/14638304/trump-fcc-free-fm-rad...