rafaelff [1] filed a request to merge koreader [2] into koreader-bin [3]: 'koreader' actually provides a binary as package source. Its content is exactly as 'koreader-bin' and is maintained by the same maintainer, so I assume there is no need for keeping both in AUR.
[1] https://aur.archlinux.org/account/rafaelff/ [2] https://aur.archlinux.org/pkgbase/koreader/ [3] https://aur.archlinux.org/pkgbase/koreader-bin/
