I tried Foliant now.
+ The UI is very cleanly done, looks much like an iPhone app.
+ UI Runs smoothly, no weird hickups.
+ it can access the file system to open books
+ remembers last read book and page you were on
+ many useful options in the very extensive settings, including custom profiles
+ full screen reading mode
+ it lets you search for and download books from a few websites, and this functionality stays nicely out of your way, when you're really just starting it up to read something you already have.
- doesn't come with a serif font, would have to find and install one to use.
- doesn't support ePub
- simply crashed upon opening graphics heavy FB2 books
- keeping my finger on the screen in full screen mode fails to get me any menu, I can neither exit full screen mode nor get out of the program without shutting down the phone...