[iPhone God App] It was found using the KanjiBox actually

KanjiBox is an offline Japanese studying application. It provides an efficient yet fun way to practice all aspects of Japanese (kana, kanji, vocab, reading, writing...) through drills, quizzes and flash cards, while providing engaging feedback through progress charts, scores and game-like "achievements" for each Japanese level.

KanjiDraw and KanaDraw add-ons harvest the full power of your device's touchscreen to guide you through proper Japanese handwriting, while detailed animated cards tell you everything you need to know on each kanji.

KanjiBox is particularly well suited for standardized test preparation (JLPT, Kanji Kentei, Ninja Academy etc.) but works great as a personal study tool too.

(check the link, below, for a video showing some of the features in action)

Main features:
• Six training levels: JLPT N5 to JLPT N1, plus an extra "Sensei" level.
• Adaptative learning: focuses on your weak points and uses spaced repetition (SRS) techniques to help you learn faster.
• Live stats: let you measure your current level and gauge your progress.
• Online scoreboards and GameCenter achievements: compete globally against all KanjiBox users!
• Additional modules help you train your handwriting on kana and kanji using the touchscreen.
• Custom Study Sets let you pick your own set of vocabulary words or kanji to focus on.
• Multiplayer mode lets you compete with friends or strangers.

• Over 6,000 kanji.
• Over 34,000 vocabulary words.
• Hiragana and katakana.

• Drill mode helps you train on kanji, vocabulary, word reading and kana.
• Quiz mode lets you log high scores and compete against friends.
• Study mode gives you customisable sets of flashcards.