New “official” Wikipedia iPhone app: Wikipedia Mobile.
Age rating of Kiwi and Wikipedia Mobile: 4+.
Age rating of Wikipanion: 17+.
Apparent difference in available content in all three apps: None.
Putative explanation from Apple senior VP Phil Schiller regarding the seeming discrepancy between Apple’s mandated 17+ rating for the Wiktionary-based dictionary app Ninjawords and other profanity-containing dictionary apps in the store which are rated 4+ or 9+: “The issue that the App Store reviewers did find with the Ninjawords application is that it provided access to other more vulgar terms than those found in traditional and common dictionaries, words that many reasonable people might find upsetting or objectionable. A quick search on Wiktionary.org easily turns up a number of offensive ‘urban slang’ terms that you won’t find in popular dictionaries such as one that you referenced, the New Oxford American Dictionary included in Mac OS X.”
Number of the aforelisted three urban slang terms indeed defined in Ninjawords: Three.
Number defined in Mac OS X’s New Oxford American Dictionary: Zero.
Sympathy, on the part of yours truly, that these terms are not in fact appropriate for young children: Much.
Consistency in the age ratings for Wikipedia-based apps in App Store: None.