It broadcasts for over an hour every day and attracts an audience of 8.5 million, according to figures released by the BBC earlier this year.
Like the iTrip, it broadcasts audio over a short range on FM frequencies.
In an effort to boost revenue from its advertisers, which include Coca-Cola, Panasonic and PepsiCo, it began streaming its broadcasts over the internet, allowing anyone in the world with a connection to tune in.
It broadcasts from venues all over the country, giving a wider reach to the great orchestras and ensembles of the UK.
It's broadcast over the radio, and then it largely disappears; or it's only heard by those who subscribe and then listen to a particular episode of a podcast series, for example.
Most English screens are in the 12-14 inch range and BBC has but one television channel over which it broadcasts 6 hours a day.
After it was broadcast over the radio in 1945 at the announcement of the death of President Franklin D. Roosevelt, it became associated with state and celebrity funerals.
Roots was reportedly the most watched miniseries of all time when it was broadcast over eight consecutive nights – which must have delighted studio bosses who feared the show would flop.
"To comply, it may broadcast over only a very short range," says Day, "perhaps less than a centimeter". In this case, a user must rest his phone right on top of the device to keep the connection, and use a headset or the loudspeaker to make and take calls.
In what was then a television first for a Hollywood film, it was broadcast over five hours (including commercials) during a single evening by CBS, preempting all of that network's regular programming for that one evening.
