10ten Japanese Reader

Features:
• Pitch accent information
• Dictionaries that update automatically every week fetching just the updated entries
• Recognition of a wide range of grammatical forms
• Conversion of yen amounts (e.g. 100億円)
• Translation of Japanese-era years into Gregorian years (e.g. 昭和５６年)
• Automatic preview of names
• Support for displaying romaji
• Support for vertical text and text in SVG images
• Support for non-English dictionaries (unfortunately no Japanese-Japanese dictionary is freely available yet)
• Up-to-date kanji data including educational and kanji kentei levels, reworked kanji components etc.
• Many settings to customize to your needs
• Localization into Simplified Chinese and Japanese

How to use:
• After installing the app it will begin downloading the dictionaries in the background. You may have to wait a few minutes before all the data is fully available.
• To look up words on a Web page, enable the extension from the Safari menu then drag the "10." circle to the word you wish to look up.
• Tap the circle once to disable looking up. Tap it again to re-enable.
• Double-tap the circle to switch its direction.
• Tap the tabs to view kanji or name information.