The earphones must be connected as they actually work as an antenna for the FM radio signal - where else do you think it is going to come from. Certainly not over the mobile phone network.
Over the mobile phone network is where it comes from on another radio app I have! Either way, it still shouldn't be a requirement, it should be a choice. If you want to use wired ones so you don't have to use mobile data, that should be a choice, not compulsory for functioning.
It doesn't. Samsung Radio is a radio, not a live radio streaming service. It sill uses an antenna. It is a choice to use wired earphones. You can select sound output in the app settings
Terrestrial broadcast radio and streaming radio are two very different transmission methods. One is the older broadcast radio signal, similar to 'dumbish' TV terrestrial broadcasts (you require an Antenna ie wired headphones) where internet radio u require network access to the internet. On ur Cell phone that's either 4G/5G terrestrial broadcasts, WiFi or perhaps teathered to a home or office wired network, think Blue Cat5/6 cables and RJ45 connectors, and teathering your cell phone to your laptop / desktop. It's not that hard, enjoy.
Yes. This is a requirement as the earphones are an antenna. However, you can select the sound output in settings; the sound doesn't have to come out of the wired earbuds
