In Accessibility, there is a Zoom function you can use. It's really tedious, though, so I'm not sure if you'll like it.
It's too bad that the current trend is tiny text that's often a grey on white. The iPad Mini really makes the text small, though. Inverting colors (also in accessibility) can also dramatically reduce eye strain while reading stuff like forums and comments.
If I were you I'd use a laptop / monitor and actually have control over the text size and colors. It's one of the pleasures of stepping outside of the walled garden.
