I blame the French. They introduced a law that forbids radio receivers that don't support DAB radio, as a way to make the newer DAB format take off. But globally, DAB never did so phone hardware don't have it. In the EU, distribution chains often cross borders and it would be too bothersome to have models with special firmware just for France — so instead, nobody gets FM-radio.
I bought last year a DAB compatible radio for my car, only to realise that it is worse than FM :)
https://www.reddit.com/r/MotoG/comments/u2dvvp/any_current_m...
https://www.amazon.com/Ulefone-Power-Armor-13-Smartphone/dp/...
https://crgsoft.com/the-list-of-2019-smartphones-that-have-f...
That was common on phones in general. Headphones acted as antenna.
If you open the FM radio app without connecting wired headphones, it'll ask you to connect it.
This was common in Android phones as well.
My current Android phone does not have headphone jack. And I can't use FM radio (although there are services that play radio over the internet, but that isn't really the same...).
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About phones which have the capability but which are disabled, I wonder if it's because of security implications.
Where I live, the allowed frequencies were from 87 MHz to 108 MHz or something. Consumer FM radios could only be tuned in this range.
That's because on frequencies outside this range, other transmissions — for example, police transmissions — might be taking place.
The aforementioned allowed range is different in different countries.
Also, in my country long long ago (like, ≈50 years ago) you needed to get the permission of the government (via a license or something) to get a radio. You couldn't just go to a store and buy one. That changed later, however.
Now that I think about it, it might have something to do with semi-secret transmissions happening on frequencies outside the allowed range.
A friend told me it's possible to take apart the radio and tune to non-standard frequencies because in most radios the "dial" to select the allowed range really works by physically jamming the dial with another block. If you remove that block, you could keep turning that dial. Haven't tried this myself, so take that with a pinch of salt.
I had that come with a cheap motorola phone (3 years ago or so)
https://www.motorola-support.com/uk-en/?page=topic/applicati...
So not ubiquitous but not that rare either.
It was very common in previous decades because it was cheaper and allowed more room in the device (the alternative was the metal “pull to extend” antennas).
Not exactly the same, but makes me reminisce the days of the iPod nano. It offered FM radio using the headphone cables as an antenna. I haven’t seen that supported anywhere since, which is a shame because I’d really like to get local stations on my phone.