I am working on a replacement (called OcherBook) for the Nickel application (the core of Kobo’s e-reader software stack). Ocher is iron (III) oxide, used for early cave paintings and pigment.

Good, Bad, and Ugly of Nickel

Some of the good points of Nickel that I want to keep or even improve upon:

  • Supports ePubs.
  • Annotations.
  • Dictionary.

Some of the bad points of Nickel that I want to remove or fix:

  • Hangs or crashes when importing certain epubs. Throw 100 epubs on a microSD card at one time, and you will likely encounter this.
  • Miscellaneous slowness: Occasional “reluctant” page turns, sluggish highlighting, …
  • Google Analytics / phoning home
  • Strong ties to an online store. I want an ebook for reading, not promoting.
  • Facebook integration and reading “awards” which seem targeted at the emo generation. Sorry, but my “book” need not caress my delicate ego.
  • FAT32 sucks: 2.x updates (2.3.1 tested) remove support for ext2 filesystems on microSD cards, and force usage of FAT32.
  • Over-zealous DRM: 2.3.1 firmware on unregistered Kobo Touch will not read non-DRM epubs. Displays ALL pages as solid black, like DRM’d books do. (Need to research: bug or over-zealous DRM?)


Currently (late 2012) a patient developer could read epubs on the Kobo Touch with this. Text rendering is simple (no superscripts, no block quotes, no CSS, etc) and images are not implemented. Navigation is only a page at a time. Installation is quite manual.


Rooting Your Kobo

You’ll need to get FTP and telnet access to your Kobo to install OcherBook. Instructions are here.


OcherBook is hosted on GitHub.

git clone git@github.com:ccoffing/OcherBook.git
cd OcherBook
git submodule init
git submodule update


Will improve these “instructions” when I actually get to that point. But the concept is encapsulated in the run-kobo.sh script:


Binary Downloads

End-users can try the binaries here. Keep in mind this is a work in progress. Also, remember that OcherBook is not yet a complete firmware installation. For safety, this installer will install OcherBook beside Nickel, but not replace it.

Updated May 10, 2014