Powerful lookup method
You can search the dictionary using any of kanji, kana, romaji or a word in one of the supported foreign languages. imiwa? will auto-magically find what you are looking for.
iOS also comes with built-in Kanji stroke recognition, use the Traditional Chinese keyboard to input directly kanji characters, this is simply amazing!
(Go to the Settings app on the device home screen and: General ↝ Keyboard ↝ Keyboards ↝ Add New Keyboard ↝ Chinese - Traditional Handwritting)