Living and working in Japan, I’ve found the Japanese dictionaryjapaneseapp.comby
renzo Inc. to be absolutely fabulous! It’s a dictionary app on my iPhone & iPad. It’s got great depth of words and allows search in English, romaji, and Kanji by SKIP Code, Components, and using Handwriting. It was a little pricy ($14 or $17 I think) but
it’s been invaluable as a resource in communications with my faculty and students. I highly recommend it.
Good luck in your search and please let me know if you have any specific questions.