I didn't know there was such a version, but if you want to read ebooks on the 4G, consider Aldiko.
I used it on my 3G and have it on my 4G now. The earlier version did not support books protected by DRM, but the newer version does. Of course, it is possible to strip off DRM. It only works with ePub format, but there is also a way to convert PDFs to ePubs.
I've read dozens of books on mine.