A modern programming language that makes developers happier.

kotlinlang

It seems I figured it out. I don't know the reason why the sample app did not work, but in my version which I tried creating alone there were multiple bugs. One of them caused throwing an exception. From Java I am used to that if I don't catch an exception the whole app crashes and I can see some log, however here no message for a thrown unchecked exception was shown and app did not crash, so everything seemed like frozen. I think it should be somehow emphasized in the tutorial, it nearly drove me crazy.