oSUMO is an offline HTML5 application for SUMO designed for Firefox OS, with added bonus of being a local application for other browsers and clients.
Most of what is interesting is inside /static. The rest is used to serve
static html pages.
You can access it right now at at http://osumo.paas.allizom.org (though this is probably very very outdated, if it works at all).
This app targets Firefox, Firefox OS, and Firefox for Android. Other platforms such as Chrome may work but is not guarenteed. Your browser must support IndexedDB and appcache.
Right now is probably not a good time to start hacking on this as most of the code is highly experimental. I would suggest you wait and give feed back on Bugzilla until the code base calms down.
Another part of this project also lives in kitsune. So take a look at that project as well.
To see some developer docs, go to https://osumo.readthedocs.org
MPLv2