In the reader software available, is there some that can reformat the text according to the zoom factor (i.e. re-wrap the text nicely)?
The html reader allows zoom and re-wrapping of the text. The PDF viewer does not allow this at the moment. The PDF viewer allows zoom and pan. See the User Manual [1], pages 38-39. PDF by definition does not reflow text; it is a fixed format. Also, you can change to horizontal orientation to enlarge the font and click on the setting “Continuous” to enlarge the font some (page 37 in the User’s Manual).