Kaku — Open Source Productivity App

Kaku is a fast, powerful Japanese dictionary that stays on top of all your apps. It uses optical character recognition (OCR) technology to recognize kanji on the device screen for you (rather than the slowww tedious process of looking up individual characters manually), making it perfect for Japanese learners who want to study by reading raw manga, play untranslated games, and so on without the hassle of switching apps.