Different times these months I had problem reading feeds article from a native iPhone application (I'm actually using MobileRSS both on iPhone and iPad). I could download all my feeds but when I accessed them I could just see photos but no text inside.
Yesterday I discovered a quick fix for this problem, that I noticed occurred any time I change the google account password.
To restore your preferred feeds reader you have just to delete your google account from it, and then re-add it again.
In this way all feeds will be correctly downloaded and they are readable again!! ;)