AReader supports txt files only, and does only what is needed: browse and remember where you were. It is a minimal ereader application. PDF support should come in future, but was announced a long time ago and is still not there.
(Source: eReaders.nl)

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FBReaderJ is a java version of fbreader. This is one of the first ereader applications that became available for the Android system and one of the best. The application has a night mode and opens directly into the libraries that you last read. The supported ebook formats fbreader is still poor. Setting font and fontsize is still insufficient. Fbreader supports epub, and fb2 OEB.

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Palm Book Reader is an application that was originally available on the Palm PDAs. Now there is an Android version available. You can put your ebooks on your SD card but Pdb file is not immediately recognized. Only when the program tells you which file it is (through menu), it is displayed correctly. Besides pdb, txt is also supported. Turning pages is quite different from the previously discussed apps. You dont hit the next page, but you scroll through a section of the ebook. This is not as long as a chapter, so you don't know how long you will be scrolling. You should always be careful that you do not scroll too far. At the end of a page are buttons that take you to the next piece of text.

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Besides a premium version there is also a free version available. Aldiko only supports epub. The bookshelf concept of the application is very nice. Loading an ebook is much faster than for example fbreader. Aldiko contains many settings for text settings and page turning can be adjusted with animations.

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