How do I know the file I am downloading is authentic and has no error?

You basically want to look at the checksum, which is publically available at https://download.kiwix.org/zim/zim_path_and_name.sha256

OR

Simply head out to browse.library.kiwix.org and simply click on SHA-256 checksum, which is listed along with download links.

How do I open PDF files?

Depending on your device there can be this weird / awkward / embarassing situation where opening a PDF file leads to a blank page. Next time, try holding CTRL when clicking on the file icon, and it should do the trick.

My phone storage is maxed out even though I deleted all ZIM files

You probably also need to empty your phone’s trash.

Can I purchase a Hotspot OS, then download and install all the content, and/or add my own content?

Yes you can. There is, in fact, an admin dashboard built for this very purpose. But bear in mind that any transfer of a new ZIM file will take place of the Raspberry’s own wifi, and depending on file size this will take some time.

Will Kiwix for Android be released on F-droid?

Yes, we plan on releasing version 4.0 on F-droid as well. You can see progress here.

Why are some links missing on Wikipedia / Wikiversity / the Wiktionary compared to the original ?

This is because those links point to categories, and these are not (yet) captured by our Mediawiki Offliner. They should be available with one of our coming releases.

If I downloaded all of Wikipedia, should I also download the more specialized subsets?

Short answer is no, you do not need to download Footbal, History, Maths by Wikipedia, as these are subsets taken from the broader Encyclopedia. There might be some differences as they are not generated on the exact same day, but you are unlikely to notice.

Can this particular website be added to the catalog?

Probably, but you will need to check that the licence allows it (usually Creative commons or GPL) and open a proper request at zim-requests.

Any plans to integrate the interlang feature?

The interlang feature on Wikipedia is what allows people to read the carrot entry in English, click on français and read the carotte article in French. We have no plans at the moment for this (admittedly) very cool, very practical feature.

Is it possible to use the zimit.kiwix.org site for sites that require a login?

Nope, well beyond what a free service can reasonably provide. Too many security constraints to handle for this to work.

Can I set SSID, password, and command shutdown for my Kiwix Hotspot ?

SSID is set to Kiwix but the admin panel allows you to set and change the wifi password. Raspberry Pi can be safely unplugged in order to shut down, as weird as that seems.