It seems like you are saying, you should get this great use case handled for you, and not have to pay for anything: not for the app or for the service.
BTW, NNW is not charging as of yet. What I was talking about in two of my messages above, is the adoption issue with disparate platforms without the availability of read-state feature. If I use NNW mobile, I'm bound to using it all the time (which is not practical). If I use it's desktop app, I'm bound to using it on my Mac all the time (again, not practical). Anyone with more than hundred or more feeds, would find issues adopting such service. I am not here to defend my likeness of NNW so I won't say anything in this regard.