One of the things I really liked about my old iPod touch was an app called Wiki Offline that included a download of Wikipedia (3 to 4.5 GB, it is constantly growing). I could update the download for 99 cents, but on my DSL lite connection it took all night to download such a huge file. And still it was missing some things. Images were out because that would greatly expand the file size, but so were tables, info boxes at the top right of most articles, as well as some types of links and numbers with units. Still, most everything that mattered was there even if I was in a subway tunnel or out on the open seas, far away from wifi or cellular service (the touch can’t get data over cellular service, but iPhones can). When I got the Nexus 7, I looked into getting a similar app, but didn’t find anything at first. Then eventually I found Kiwix, but it involved a 16 GB download of Wikipedia (on a 32 GB Nexus 7 I didn’t have room at first, but recently I wiped out the memory to speed it up and it would just fit).
Kiwix is a free app developed by some people who wanted to make all of the contents of Wikipedia available offline, either as a CD ROM or a file so that, for instance, children in remote schools away from an internet connection could still benefit from Wikipedia. It wasn’t so much an app as a computer program for Windows or Linux, but later on they made an Android version. They never got going on an iOS version although their website says that is something they would like to do. However, they have a logo for iOS 5 on that page (Apple is now on iOS 8), so I’m thinking that effort isn’t going anywhere fast.
Although I had the app on my Nexus 7, I never downloaded the giant file to go along with it. But now I have a faster internet connection, more storage available on the Nexus 7, and no alternative on my new iPod touch, so I downloaded the 16 GB version. It still doesn’t have images (that file is 48 GB and probably only includes thumbnails), but the tables, units, even the references are all there and it looks just like Wikipedia in a browser. In fact Kiwix uses Mozilla’s open source browser and tacks on the ability to download and read archive files in the .ZIM format.
Having the contents of Wikipedia is one thing, but it’s an awfully big haystack, so you have to have a way to search it. Some of the offline wiki apps really struggle with that. I had one where you had to enter the title of the article exactly or it couldn’t find what you were looking for. Wiki Offline had a pretty good index that included all of the redirects. Kiwix seems okay, but maybe not quite as good at searching as Wiki Offline. I was looking for Battle of the Philippine Sea and it gave up when I didn’t capitalize Philippine. Also, if I get out of the app and go back, it starts up with the starting page instead of remembering where I was. And while I can zoom in to a page, I can’t just increase the text size (though you can do this in the desktop version). Still, it’s free.
Since I had already done the hard part of downloading the giant file, I transferred a copy to my laptop and downloaded the Windows version of Kiwix. So now I also have Kiwix on my laptop just in case I’m away from wifi.