WikiOnBoard is a viewer for zim files, a file format for wiki content supported by the Wikimedia foundation.

Where to get eBooks?

Sites where you can find various zim files, including the Wikipedia

  • has Wikipedia-Versions in many different languages.


  • On the wikipedia website you can use “Print/export”, “Create a Book” to generate an eBook of selected pages. For use with WikiOnBoard you have to select “openZim” as format. Here you can find more information.

It is strongly recommended to download zim files to your desktop PC and copy them to the phone’s memory card using the phones USB connection or a memory card reader. Downloading zim files directly to your phone is not recommended as the files are typically very large. Note that if the file is larger than 2 GB, you definitely have to use a PC for downloading it as it is not possible to download it directly to the phone.

Handling of files larger than 2GB

Unfortunately, current Symbian mobile phones do not support files which are larger than 2GB. To workaround this, you can split these files into chunks of less than 2 GB each to work around this issue.

In order to do this, you will need a file splitter tool. On Windows you can use for example FFSJ-Lite.

First, open the source zim file in the split tool and perform the split.

Then rename the generated files so that the first file has the extension .zimaa, the second .zimab and so on.

For example, if you split a file called wikipedia.zim with FFSJ-Lite, you have to rename the generated files as follows:

wikipedia.zim.001 must be renamed to wikipedia.zimaa, wikipedia.zim.002 to wikipedia.zimab, wikipedia.zim.003 to wikipedia.zimac, and wikipedia.zim.004 to wikipedia.zimad.

Then these files must be stored on the memory card in a common folder. To open the Wikipedia, any of these files can be selected in the app.

WikiOnBoard 2 on Nokia Belle

With WikiOnBoard 2 on Nokia Belle devices the 2 GB limitation has been fixed. The file size limit is now 4 GB, which is also the maximum file size of the file system used on SDHC memory cards.

If you need to split a file, because it’s larger than 4 GB, you should anyway split it in chunks of less than 2 GB. There is no real drawback in having smaller chunks, and the files are then compatible with older operating system versions as well.

However, if you use a Nokia Belle device with WikiOnBoard 2, and you have a zim file which is larger than 2 GB, but less than 4 GB, you can omit the split step and directly put it on your mobile phone.

Note, that actually Belle and WikiOnBoard 2 is not necessarily the only configuration with 4 GB file support. For example I know that it works with WikiOnBoard 1 on Nokia Belle as well. However, as there may be other relevant dependencies, and there is anyway not much point in using an old WikiOnBoard version on Nokia Belle, I don’t want to promise this. I believe that 4 GB files won’t work with older OS versions like Nokia Anna. If you want to try it out anyway, I’d appreciate if you let me know you results via e-mail.