[mariosipad]

@haertig

Just like you I have not been able to upload (in any conceivable way) an audiobook file (m4b and or mp3) to the iBooks app without iTunes.

However it is possible to play audiobook files with other (free and paid) apps on an iPhone or iPad. Most apps only seem to connect to fixed audiobook libraries on the web but some should be able to use audiobook files with Dropbox, iCloud, etc.
It should even be possible to upload files through a http connection. I would like smb (samba) access capabilities (but have not found so far).

2 apps that should be able to do this are:
- Bookmobile (60 days free -> try it out, afterwards U$D 4 as in app purchase for the full version)
- Bound U$D 4
They can be found in the App Store.

As a side question: how did you convert mp3 files to m4b file(s). And is that with or without chapters and art/covers?

Edit: Bookmobile works for me and my workflow:
My workflow is:
- do what I have to do to make an audiobook
- put the audiobook in a samba share on my debian server (or put it in dropbox if copyrights are ok)f
- use the iOS app FileBrowser to connect to the samba share, select the audiobook
- in FileBrowser use the option "open in ...." choose Bookmobile
- audiobook is visible in Bookmobile (file, chapters and cover art!)
In short: it works for me. (so far......;-) )