Ranging from beginner level to advanced these Japanese Dictionaries are the best apps for the iPhone. Hopefully you'll find one that fits your budget and will help you advance in your study of Japanese.

iEijiro is a $9 E-J / J-E Dictionary 2 million Is targeted towards Japanese. Its strong in tons of example phrases and really covers them well. Keeps a list of your recent lookups. Searching is only in Japanese you must use the kanji but you can type in japanese iphone keyboard in romaji and switch. Aadd anything you wish for a flashcard by clicking the plus sign. Flashcards is just a list of your favorites. Flascards can be sorted by ascending or descending order. Quiz section you use your flashcards which you can do in random or sequential order. It'll display kanji on top and click show button to reveal defintion on bottom half portion of the screen which is scrollable.

Kotoba! is a free E-J / J-E Dictionary is not too shabby for being free. Can toggle on/off French, German, Russian definitions and set Primary Language. Romaji display can be set to on or off. Has a common words sensitivy slider. Can use iPhone's built-in Chinese handwriting recognition search for kanji. Shows a small set of kanji stroke order animation for a few of the kanjis.

Japanese is a $20 E-J / J-E Dictionary 115,000 target audience for this is definitely for non-native Japanese. Has a great breakdown of lists and searchable within most of them all of them. Hiragana & Katana, Kanji, Lists (Classification, Counter, Expressions, Proverbs, Vocabulary Lists {added by you} and JLPT. Has full screen stroke order animation. For a dictionary based on the free edict like Kotoba! which is free this seems to be tad overpriced for the just the classifications and tad bit of UI enhancement.

PRG Eng-Jpn Dictionary is $8 E-J 85,000 entries, J-E 100,000 entries is for native Japanese speakers. However, it's quite good if you can read a decent amount of kanji. Has 3 levels of zoom which can be done at anytime with pinch motion or by double tapping. Can navigate to next | previous by pressing the arrow keys. Also can rotate to landscape mode which removes the arrow keys and you can scroll through looking for you word by swiping. Searching can not be done by romaji only English words when using ABC and you can searching by hiragana or kanji. However, when searching by kanji the results will still show the hiragana in the search results pane. Definitions are thourough with tons of examples sprinkled through out. The help section of PRG Eng-Jpn Dictionary is probably the most detailed explanations I've seen for any dictionary app yet. Has bookmarks you can save by clicking the + (plus) button. Booksmarks can easily be deleted either with the edit button then clicking ones or the swipe left to delete just one. No history function so be sure to bookmark anyones you might need in the future. Has many tenses of the words in Japanese and English. Usually that tense will be part of the main word so it'll briefly, for a second, flash the yellow part so your eyes can quickly focus on the tense your seeking. Crossword is included with 6,000 words / clues.

ptsEijiro Viewer is a $10 E-J dictionary try demo (has words A and B). ptsEijiro has a Bookmarks and a History section. Uses same dictionary content as iEjirio (see near top of page). Can view in landscape too.

ptsWeaijiro Viewer is a $7J-E dictionary just like it's sister ptsEijiro has a Bookmarks and a History section.

SlovoEd Compact E-J / J-E Dictionary is $10 10,029 entires with 5,000 voice pronunciations. I was told Oxford Beginner's E-J / J-E Dictionary is $15 is same one content wise it's just branding is the only difference. So I'm reviewing SlovoEd Compact which in the info section it says Oxford Beginner's Japanese Dicitonary so yep it's the same content. E-J 5,306 entires and J-E 3,768 entries. There is a toggle button (has two arrows) to switch from E-J and J-E mode. When searching in J-E mode you can using romaji, hiragana or kanji. Seaching in English you can search using * as a wildcard letters or ? as a single wild letter which is nice. There is a similar spelling search feature too (see screenshot searching for prevail). Sound icons have a male voice speaking the English words (no Japanese words have sound just English). Tap left or right arrow navigate in your history of words. The History section contains your kanji, hiragana and English words for easy quick lookup. This is a beginner's dictionary so they've stripped lots of definitions content and many times only a single definition is given. See tomodachi - friend screenshot for an example. For those learning Japanese they have added furigana / ruby for the example sentences which is probably the biggest selling point of this dictionary.. In the English many words have a button you tap see to Word Forms which shows many tenses of that paticular word. Not all make sense like toilet (They would be toileting). I've heard of (They would be loitering) but not toileting. But as long as you know what is and what isn't proper English it's a welcome addition and a handy reference to have. Overall it's decent dictionary but really sparse on content at times but that is intended.

The Wisdom E-J / J-E Dictionary is $24 90,000 words (major update forthcoming so will revist then). The content on here is supreme. So many example sentences it'll make your head explode. I tried to capture a few screens but it'll take about 25 screenshots (yes I counted) just to show all of content under the word BEST for instance. Search in english, kana or kanji. There are a few pronunciations sprinkled throughout with even some phrases too. Takes 2 seconds for sound to play. UI issues need some mentioning. In portrait mode it'll only show 3 at a time which you need to scroll. Clicking on the Full Screen button (square with 2 arrows) gets rid of the list mode. Zooming is done with pinch but it's pretty much useless as the text doesn't wrap and scrolling right then left then down then right then left isn't pratical. Best way to show text in biggest size is to use landscape mode as seen in the last two screenshots. Hopefully the UI will get reworked and when it does Wisdom will be one of the best Japanese Dictionaries for iphone as content is king. Now if they could make this dictionary's content fully hyperlinked like their encylopedia app then it'll be an absolutely killer dictionary.

Longman E-J Dictionary is $21 102,000 words, 83,000 example sentences (2/23)

Japanese Dictionary Pro is $5 contains wordnet dictionary too for full english definitions (2/23)

Updated March 4, 2009

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