At the moment, we cache the last 10 visited articles in memory (in the Java VM heap). This is probably a bad idea, since the size of each article is not predictable, and the VM size varies greatly across different devices and Android versions (it's as small as 24MB on older devices).

One straightforward solution to this would be to cache the pages by writing them to local storage. We could probably reuse our logic for Saved Pages, and automatically "save" the page as soon as it's loaded. That way, it will be cached by default, and if the user actually wants to save the page, all we have to do is add the entry to the saved-pages sqlite table.