UPDATE: The deckbuilder at se.gondorian.com has had EXPERIMENTAL support added for offline use. This works by caching all the files on your device/computer and then having your web browser defer to that cache if there is no internet connection. It works for me on iPad Air Safari. Please share your experiences with it, if you try this feature. (On iOS, make sure you turn off Private Browsing, if you're normally into that kind of thing, since caching will be disabled otherwise.)
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