I have android app apk on my USB, I inserted it in my LG smart tv, it shows me USB device, but apk is not visible... Any ideas what's the issue with it?
Here is a great guide how to do that, if your TV is android TV: https://pedronveloso.com/how-to-install-an-apk-on-android-tv/
Have you enabled 'unknown sources' from security and restrictions settings?