Evopedia is an offline wikipedia viewer. See the official site : http://www.evopedia.info/ This application is developed in HTML5/Javascript, with Firefox OS as the primary target.
You can install the latest stable version from the Mozilla Marketplace : https://marketplace.firefox.com/app/evopedia/
You can search among the article titles, and read any of them without any Internet access. All the content of wikipedia is inside your device (except the images). It also works with Wiktionary and Wikivoyage. If your Internet access is expensive/rare/slow/unreliable/watched/censored, you still can browse this amazing amount of knowledge and culture.
It uses wikipedia archives located at http://dumpathome.evopedia.info/dumps/finished You have to first download one of them (with a Bittorrent client) and store it on your SD-card.
This application is released under the GPL v3 license. See http://www.gnu.org/licenses/ or the included LICENSE-GPLv3.txt file The source code can be found at https://github.com/mossroy/evopedia-html5
Unit tests can be run by opening tests.html file