Morphe is your friend. The instructions to use morphe on e.g. joey for reddit are everywhere, and they all wind up in the same place: install redreader, get your API token, tell Morphe, move on with your life.
I want my specific reader for some UI which I don't find in other reddit apps. Like touch/hold to show fullscreen on image, touch/hold to show comment thread precis.
I downloaded and installed it. The specific two UI actions I wanted and mentioned are not implemented. I don't care how powerful it is, these UI approaches are why I chose and use joey.
So apps like Continuum now they need to spoof their identity as RedReader, if you use them with your own API key. Sign out and sign in again and confirm RedReader access.
Also anonymous unauthenticated .json access is now blocked.