Of these four e-reader apps, Moon+ Reader gives you the finest-grained control over display settings and the greatest number of options for configuring control gestures, along with a couple of unusual and useful features.
Moon+ Reader's home screen lets you browse a bookshelf of files you've opened, browse your file system or open a list of five online catalogs, to which you can add your own. The Pro version has a Statistics page that shows the number of books on your shelf, read books, reading hours and pages turned.
The reading experience in Moon+ Reader stacks up to any e-reader and goes even further. The app's status bar displays your reading progress not only for the document as a whole, but also within the current section or chapter. However, I did notice one flaw in document rendering: The blockquote tag in HTML documents is not properly indented. FBReader has the same problem, but Cool Reader gets it right.
Tapping on the center of the screen or pressing the menu button while you're reading a book displays a progress slider at the top of the screen that you can use to move around within a document. At the same time, an icon bar at the bottom lets you change display options, start autoscrolling, access bookmarks and the table of contents, and change all of the app's settings.
Moon+'s settings are grouped into visual options, control options and miscellaneous. The visual options let you choose from among dozens of typefaces, including serif, sans serif and monospace, bold and italic, and non-Latin fonts, many for Indian languages. Sliders let you specify any solid color for the type or background, or you can pick from 10 background images, all of which are suitably muted.
You can adjust font sizes, but unlike the other apps, which seem to measure font size in pixels, Moon+ seems to use points), and lets you adjust fonts in increments of 0.1 points. You can specify the width of the left, right, top and bottom margins in single-pixel increments. The font and margin controls are plus and minus buttons, so you can make things a little bigger or smaller without having to choose a particular number from a list. Also, you can animate page turns in seven different ways, or not at all.
You can save all your visual options as a theme, so different people who use the same device can view books just the way they like. The app comes with a dozen preset themes, rather than the binary day/night choices common in other apps.
The control options let you specify portrait or landscape orientation, or have the software sense which way you're holding the phone. You can also specify actions to take when you tap the screen in different places, press various keys or make finger gestures.
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