The current feedly apps (iOS and Android) do not offer offline article caching.
This is a feature we are looking into.
If you’re looking for offline support, some feedly partner apps support it (eg.Reeder and Newsify on iOS, or Press on Android).
Those apps are powered by the feedly Cloud API and will seamlessly recreate your reading environment (all your feeds are sync’ed from feedly when you login).
To explore the feedly partner apps and their features, visit http://www.feedly.com/apps.htmlSun W Kim commented
Byline costs money for iOS but has offline capability up to 2000 items. It used to work with google reader but now works with feedly
4 votesSun W Kim commented
I just scrolled down through 50 articles using the middle view icon and it still is marked as unread. Maybe this is related. Google Reader would mark articles as read as you scrolled past them. If I recall correctly, there was some sort of visual indicator to tell you which article it selected, so you knew up to which article Google Reader consider was read. I don't know how difficult it would be to program, but I imagine how long you hover over an article could be an indicator of a read article... or at the very least, the first visible article at the top would be marked as read.