I might be biased as an app developer, but if apps are done properly they can provide a much deeper experience for users. I understand your point that most things can be done in a cross platform manner, however in my 10 years of mobile development experience, cross platform is great for 90% of things, sucks at 5%, and simply cannot do the last 5%. If your tech needs fall into any of the 5's then a native app is simply the better solution.

They killed flash because it was a bug riddled, security nightmare, owned by Adobe, (one of the greediest corporations in existence). I will never understand the flash nostalgia, good riddance.