The app is only a 3MB download and can be accessed via the AnroidPit market, in Amazon and on the official site. I originally got mine from the Play Store but it's curious that it is now not available there anymore. I have emailed a query to the developer about this and I will include an update at the bottom of the post once I've received a reply. For now, the alternative site download links will do.
Using the app is fairly easy. The Home dashboard of the app shows you your previously added books. The app doesn't yet have the functionality to add ebooks in your device automatically to the virtual bookshelf. Here's hoping it would have one soon.
To read a book, just click on one and wait for it to load. From here on you can play around with the various customization options of the app according to your most comfortable reading preferences.
You can change the theme of the book. When I mention theme, this means the color of the page and the fonts. There are already some presets you can choose from.
If you want to further get more control in personalizing the app, you can individually change the pages and the fonts.
You can get the book info in the properties and you can search for a particular word inside the ebook.
Here's the view for the comic books. Initial launch to a comic takes you to a page with a bottom slider for the available pages. This disappears as soon as you begin to read.
Download the .apk for this app.
AndroidPit market Link: Moon+ Reader Free
AndroidPit market Link: Moon+ Reader Pro
Official site for the app.