Is there a way to check device’s network connection in common code or we have to write platform specific code? Are there any working examples?

that would be interesting to see if there is..

You have to write platform specific code, but you're free to expect/actual or abstract it behind an interface so that it's available in common. Also, there's no true way to check connectivity except to make a call. Nearly ever layer of the network stack is designed to lie to you about connectivity.

I would not recommend that after a cursory look

Let’s take the scenario below: “The device performs a call and the call fails with a http error, for example UnknownHostException.” • Can we safely assume that the device has no internet connection? Also: The main reason that we need this piece of info is to have a proper error handling.

Depends on whether you control every host that could possibly be connected to or not. And even then you're making assumptions about the availability of DNS and a pathway through the internet.

Exactly! So we need to have the device’s network info. It would be really convenient if Ktor could throw a relevant exception out of the box. Btw: • the Ktor iOS client returns a message in Throwable and indicates that there is no internet connection. No error code though, just a message. • The Ktor okHttp client returns an UnknownHostException.

The network info doesn't provide this information. It is, at best, a guess. It doesn't deal with broken DNS, captive portals, and broken routes all of which will report a fully working connection. Moreover, even when a successful connection could be made the network info may report problems.

I see your point, so at best we should catch all connection related exceptions and display a general connection error to the user. We cannot accurately display a network specific error like: “The device appears to be offline. Make sure you have a connection and try again.” The initial need to check device’s network connection seems to be in the wrong direction. Thanks for your support! 🙂

You can react to an unknown host by checking and then using the "appears to be" wording. But just know that it might also be a captive portal or something else.