Listening to FM Radio Offline

Neither the iPhone Xs nor the 6s has a built-in FM radio tuner. Most smartphones, including the iPhone, do not include a physical FM radio because it's assumed users will stream radio through apps over the internet.

However, some Android phones do have an FM chip that can be used to receive local FM signals without an internet connection, but it is not a common feature. This is also subject to the phone manufacturer deciding to activate it.

As an iPhone user, if you want to listen to FM radio without an internet connection, you might need to use an external device, like a portable FM radio. Another option is to use a dongle that can plug into your iPhone and provide it with an FM radio tuner, though this is subject to compatibility with the iPhone's hardware and OS.

It's also worth mentioning that this information may change as technology evolves. Always check with the current product specifications or Apple's customer service for the most accurate and up-to-date information.